SemaDecl.cpp revision 7d384dd5ace9ae9a22a69e700d2cacb256bc6c69
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "Lookup.h" 16#include "clang/AST/APValue.h" 17#include "clang/AST/ASTConsumer.h" 18#include "clang/AST/ASTContext.h" 19#include "clang/Analysis/CFG.h" 20#include "clang/AST/CXXInheritance.h" 21#include "clang/AST/DeclObjC.h" 22#include "clang/AST/DeclTemplate.h" 23#include "clang/AST/ExprCXX.h" 24#include "clang/AST/StmtCXX.h" 25#include "clang/AST/StmtObjC.h" 26#include "clang/Parse/DeclSpec.h" 27#include "clang/Parse/ParseDiagnostic.h" 28#include "clang/Parse/Template.h" 29#include "clang/Basic/PartialDiagnostic.h" 30#include "clang/Basic/SourceManager.h" 31#include "clang/Basic/TargetInfo.h" 32// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 33#include "clang/Lex/Preprocessor.h" 34#include "clang/Lex/HeaderSearch.h" 35#include "llvm/ADT/BitVector.h" 36#include "llvm/ADT/STLExtras.h" 37#include <algorithm> 38#include <cstring> 39#include <functional> 40#include <queue> 41using namespace clang; 42 43/// getDeclName - Return a pretty name for the specified decl if possible, or 44/// an empty string if not. This is used for pretty crash reporting. 45std::string Sema::getDeclName(DeclPtrTy d) { 46 Decl *D = d.getAs<Decl>(); 47 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 48 return DN->getQualifiedNameAsString(); 49 return ""; 50} 51 52Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 53 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 54} 55 56/// \brief If the identifier refers to a type name within this scope, 57/// return the declaration of that type. 58/// 59/// This routine performs ordinary name lookup of the identifier II 60/// within the given scope, with optional C++ scope specifier SS, to 61/// determine whether the name refers to a type. If so, returns an 62/// opaque pointer (actually a QualType) corresponding to that 63/// type. Otherwise, returns NULL. 64/// 65/// If name lookup results in an ambiguity, this routine will complain 66/// and then return NULL. 67Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 68 Scope *S, const CXXScopeSpec *SS, 69 bool isClassName) { 70 // C++ [temp.res]p3: 71 // A qualified-id that refers to a type and in which the 72 // nested-name-specifier depends on a template-parameter (14.6.2) 73 // shall be prefixed by the keyword typename to indicate that the 74 // qualified-id denotes a type, forming an 75 // elaborated-type-specifier (7.1.5.3). 76 // 77 // We therefore do not perform any name lookup if the result would 78 // refer to a member of an unknown specialization. 79 if (SS && isUnknownSpecialization(*SS)) { 80 if (!isClassName) 81 return 0; 82 83 // We know from the grammar that this name refers to a type, so build a 84 // TypenameType node to describe the type. 85 // FIXME: Record somewhere that this TypenameType node has no "typename" 86 // keyword associated with it. 87 return CheckTypenameType((NestedNameSpecifier *)SS->getScopeRep(), 88 II, SS->getRange()).getAsOpaquePtr(); 89 } 90 91 LookupResult Result(*this, &II, NameLoc, LookupOrdinaryName); 92 LookupParsedName(Result, S, SS, false); 93 94 NamedDecl *IIDecl = 0; 95 switch (Result.getResultKind()) { 96 case LookupResult::NotFound: 97 case LookupResult::FoundOverloaded: 98 case LookupResult::FoundUnresolvedValue: 99 return 0; 100 101 case LookupResult::Ambiguous: 102 // Recover from type-hiding ambiguities by hiding the type. We'll 103 // do the lookup again when looking for an object, and we can 104 // diagnose the error then. If we don't do this, then the error 105 // about hiding the type will be immediately followed by an error 106 // that only makes sense if the identifier was treated like a type. 107 if (Result.getAmbiguityKind() == LookupResult::AmbiguousTagHiding) { 108 Result.suppressDiagnostics(); 109 return 0; 110 } 111 112 // Look to see if we have a type anywhere in the list of results. 113 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 114 Res != ResEnd; ++Res) { 115 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 116 if (!IIDecl || 117 (*Res)->getLocation().getRawEncoding() < 118 IIDecl->getLocation().getRawEncoding()) 119 IIDecl = *Res; 120 } 121 } 122 123 if (!IIDecl) { 124 // None of the entities we found is a type, so there is no way 125 // to even assume that the result is a type. In this case, don't 126 // complain about the ambiguity. The parser will either try to 127 // perform this lookup again (e.g., as an object name), which 128 // will produce the ambiguity, or will complain that it expected 129 // a type name. 130 Result.suppressDiagnostics(); 131 return 0; 132 } 133 134 // We found a type within the ambiguous lookup; diagnose the 135 // ambiguity and then return that type. This might be the right 136 // answer, or it might not be, but it suppresses any attempt to 137 // perform the name lookup again. 138 break; 139 140 case LookupResult::Found: 141 IIDecl = Result.getFoundDecl(); 142 break; 143 } 144 145 assert(IIDecl && "Didn't find decl"); 146 147 QualType T; 148 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 149 DiagnoseUseOfDecl(IIDecl, NameLoc); 150 151 // C++ [temp.local]p2: 152 // Within the scope of a class template specialization or 153 // partial specialization, when the injected-class-name is 154 // not followed by a <, it is equivalent to the 155 // injected-class-name followed by the template-argument s 156 // of the class template specialization or partial 157 // specialization enclosed in <>. 158 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) 159 if (RD->isInjectedClassName()) 160 if (ClassTemplateDecl *Template = RD->getDescribedClassTemplate()) 161 T = Template->getInjectedClassNameType(Context); 162 163 if (T.isNull()) 164 T = Context.getTypeDeclType(TD); 165 166 if (SS) 167 T = getQualifiedNameType(*SS, T); 168 169 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 170 T = Context.getObjCInterfaceType(IDecl); 171 } else if (UnresolvedUsingTypenameDecl *UUDecl = 172 dyn_cast<UnresolvedUsingTypenameDecl>(IIDecl)) { 173 // FIXME: preserve source structure information. 174 T = Context.getTypenameType(UUDecl->getTargetNestedNameSpecifier(), &II); 175 } else { 176 // If it's not plausibly a type, suppress diagnostics. 177 Result.suppressDiagnostics(); 178 return 0; 179 } 180 181 return T.getAsOpaquePtr(); 182} 183 184/// isTagName() - This method is called *for error recovery purposes only* 185/// to determine if the specified name is a valid tag name ("struct foo"). If 186/// so, this returns the TST for the tag corresponding to it (TST_enum, 187/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 188/// where the user forgot to specify the tag. 189DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 190 // Do a tag name lookup in this scope. 191 LookupResult R(*this, &II, SourceLocation(), LookupTagName); 192 LookupName(R, S, false); 193 R.suppressDiagnostics(); 194 if (R.getResultKind() == LookupResult::Found) 195 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsSingleDecl(Context))) { 196 switch (TD->getTagKind()) { 197 case TagDecl::TK_struct: return DeclSpec::TST_struct; 198 case TagDecl::TK_union: return DeclSpec::TST_union; 199 case TagDecl::TK_class: return DeclSpec::TST_class; 200 case TagDecl::TK_enum: return DeclSpec::TST_enum; 201 } 202 } 203 204 return DeclSpec::TST_unspecified; 205} 206 207bool Sema::DiagnoseUnknownTypeName(const IdentifierInfo &II, 208 SourceLocation IILoc, 209 Scope *S, 210 const CXXScopeSpec *SS, 211 TypeTy *&SuggestedType) { 212 // We don't have anything to suggest (yet). 213 SuggestedType = 0; 214 215 // FIXME: Should we move the logic that tries to recover from a missing tag 216 // (struct, union, enum) from Parser::ParseImplicitInt here, instead? 217 218 if (!SS) 219 Diag(IILoc, diag::err_unknown_typename) << &II; 220 else if (DeclContext *DC = computeDeclContext(*SS, false)) 221 Diag(IILoc, diag::err_typename_nested_not_found) 222 << &II << DC << SS->getRange(); 223 else if (isDependentScopeSpecifier(*SS)) { 224 Diag(SS->getRange().getBegin(), diag::err_typename_missing) 225 << (NestedNameSpecifier *)SS->getScopeRep() << II.getName() 226 << SourceRange(SS->getRange().getBegin(), IILoc) 227 << CodeModificationHint::CreateInsertion(SS->getRange().getBegin(), 228 "typename "); 229 SuggestedType = ActOnTypenameType(SourceLocation(), *SS, II, IILoc).get(); 230 } else { 231 assert(SS && SS->isInvalid() && 232 "Invalid scope specifier has already been diagnosed"); 233 } 234 235 return true; 236} 237 238// Determines the context to return to after temporarily entering a 239// context. This depends in an unnecessarily complicated way on the 240// exact ordering of callbacks from the parser. 241DeclContext *Sema::getContainingDC(DeclContext *DC) { 242 243 // Functions defined inline within classes aren't parsed until we've 244 // finished parsing the top-level class, so the top-level class is 245 // the context we'll need to return to. 246 if (isa<FunctionDecl>(DC)) { 247 DC = DC->getLexicalParent(); 248 249 // A function not defined within a class will always return to its 250 // lexical context. 251 if (!isa<CXXRecordDecl>(DC)) 252 return DC; 253 254 // A C++ inline method/friend is parsed *after* the topmost class 255 // it was declared in is fully parsed ("complete"); the topmost 256 // class is the context we need to return to. 257 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 258 DC = RD; 259 260 // Return the declaration context of the topmost class the inline method is 261 // declared in. 262 return DC; 263 } 264 265 if (isa<ObjCMethodDecl>(DC)) 266 return Context.getTranslationUnitDecl(); 267 268 return DC->getLexicalParent(); 269} 270 271void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 272 assert(getContainingDC(DC) == CurContext && 273 "The next DeclContext should be lexically contained in the current one."); 274 CurContext = DC; 275 S->setEntity(DC); 276} 277 278void Sema::PopDeclContext() { 279 assert(CurContext && "DeclContext imbalance!"); 280 281 CurContext = getContainingDC(CurContext); 282} 283 284/// EnterDeclaratorContext - Used when we must lookup names in the context 285/// of a declarator's nested name specifier. 286void Sema::EnterDeclaratorContext(Scope *S, DeclContext *DC) { 287 assert(PreDeclaratorDC == 0 && "Previous declarator context not popped?"); 288 PreDeclaratorDC = static_cast<DeclContext*>(S->getEntity()); 289 CurContext = DC; 290 assert(CurContext && "No context?"); 291 S->setEntity(CurContext); 292} 293 294void Sema::ExitDeclaratorContext(Scope *S) { 295 S->setEntity(PreDeclaratorDC); 296 PreDeclaratorDC = 0; 297 298 // Reset CurContext to the nearest enclosing context. 299 while (!S->getEntity() && S->getParent()) 300 S = S->getParent(); 301 CurContext = static_cast<DeclContext*>(S->getEntity()); 302 assert(CurContext && "No context?"); 303} 304 305/// \brief Determine whether we allow overloading of the function 306/// PrevDecl with another declaration. 307/// 308/// This routine determines whether overloading is possible, not 309/// whether some new function is actually an overload. It will return 310/// true in C++ (where we can always provide overloads) or, as an 311/// extension, in C when the previous function is already an 312/// overloaded function declaration or has the "overloadable" 313/// attribute. 314static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 315 if (Context.getLangOptions().CPlusPlus) 316 return true; 317 318 if (isa<OverloadedFunctionDecl>(PrevDecl)) 319 return true; 320 321 return PrevDecl->getAttr<OverloadableAttr>() != 0; 322} 323 324/// Add this decl to the scope shadowed decl chains. 325void Sema::PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext) { 326 // Move up the scope chain until we find the nearest enclosing 327 // non-transparent context. The declaration will be introduced into this 328 // scope. 329 while (S->getEntity() && 330 ((DeclContext *)S->getEntity())->isTransparentContext()) 331 S = S->getParent(); 332 333 // Add scoped declarations into their context, so that they can be 334 // found later. Declarations without a context won't be inserted 335 // into any context. 336 if (AddToContext) 337 CurContext->addDecl(D); 338 339 // Out-of-line function and variable definitions should not be pushed into 340 // scope. 341 if ((isa<FunctionTemplateDecl>(D) && 342 cast<FunctionTemplateDecl>(D)->getTemplatedDecl()->isOutOfLine()) || 343 (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isOutOfLine()) || 344 (isa<VarDecl>(D) && cast<VarDecl>(D)->isOutOfLine())) 345 return; 346 347 // If this replaces anything in the current scope, 348 IdentifierResolver::iterator I = IdResolver.begin(D->getDeclName()), 349 IEnd = IdResolver.end(); 350 for (; I != IEnd; ++I) { 351 if (S->isDeclScope(DeclPtrTy::make(*I)) && D->declarationReplaces(*I)) { 352 S->RemoveDecl(DeclPtrTy::make(*I)); 353 IdResolver.RemoveDecl(*I); 354 355 // Should only need to replace one decl. 356 break; 357 } 358 } 359 360 S->AddDecl(DeclPtrTy::make(D)); 361 IdResolver.AddDecl(D); 362} 363 364bool Sema::isDeclInScope(NamedDecl *&D, DeclContext *Ctx, Scope *S) { 365 if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D)) { 366 // Look inside the overload set to determine if any of the declarations 367 // are in scope. (Possibly) build a new overload set containing only 368 // those declarations that are in scope. 369 OverloadedFunctionDecl *NewOvl = 0; 370 bool FoundInScope = false; 371 for (OverloadedFunctionDecl::function_iterator F = Ovl->function_begin(), 372 FEnd = Ovl->function_end(); 373 F != FEnd; ++F) { 374 NamedDecl *FD = F->get(); 375 if (!isDeclInScope(FD, Ctx, S)) { 376 if (!NewOvl && F != Ovl->function_begin()) { 377 NewOvl = OverloadedFunctionDecl::Create(Context, 378 F->get()->getDeclContext(), 379 F->get()->getDeclName()); 380 D = NewOvl; 381 for (OverloadedFunctionDecl::function_iterator 382 First = Ovl->function_begin(); 383 First != F; ++First) 384 NewOvl->addOverload(*First); 385 } 386 } else { 387 FoundInScope = true; 388 if (NewOvl) 389 NewOvl->addOverload(*F); 390 } 391 } 392 393 return FoundInScope; 394 } 395 396 return IdResolver.isDeclInScope(D, Ctx, Context, S); 397} 398 399static bool ShouldDiagnoseUnusedDecl(const NamedDecl *D) { 400 if (D->isUsed() || D->hasAttr<UnusedAttr>()) 401 return false; 402 403 if (const ValueDecl *VD = dyn_cast<ValueDecl>(D)) { 404 if (const RecordType *RT = VD->getType()->getAs<RecordType>()) { 405 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl())) { 406 if (!RD->hasTrivialConstructor()) 407 return false; 408 if (!RD->hasTrivialDestructor()) 409 return false; 410 } 411 } 412 } 413 414 return (isa<VarDecl>(D) && !isa<ParmVarDecl>(D) && 415 !isa<ImplicitParamDecl>(D) && 416 D->getDeclContext()->isFunctionOrMethod()); 417} 418 419void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 420 if (S->decl_empty()) return; 421 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 422 "Scope shouldn't contain decls!"); 423 424 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 425 I != E; ++I) { 426 Decl *TmpD = (*I).getAs<Decl>(); 427 assert(TmpD && "This decl didn't get pushed??"); 428 429 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 430 NamedDecl *D = cast<NamedDecl>(TmpD); 431 432 if (!D->getDeclName()) continue; 433 434 // Diagnose unused variables in this scope. 435 if (ShouldDiagnoseUnusedDecl(D)) 436 Diag(D->getLocation(), diag::warn_unused_variable) << D->getDeclName(); 437 438 // Remove this name from our lexical scope. 439 IdResolver.RemoveDecl(D); 440 } 441} 442 443/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 444/// return 0 if one not found. 445ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 446 // The third "scope" argument is 0 since we aren't enabling lazy built-in 447 // creation from this context. 448 NamedDecl *IDecl = LookupSingleName(TUScope, Id, LookupOrdinaryName); 449 450 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 451} 452 453/// getNonFieldDeclScope - Retrieves the innermost scope, starting 454/// from S, where a non-field would be declared. This routine copes 455/// with the difference between C and C++ scoping rules in structs and 456/// unions. For example, the following code is well-formed in C but 457/// ill-formed in C++: 458/// @code 459/// struct S6 { 460/// enum { BAR } e; 461/// }; 462/// 463/// void test_S6() { 464/// struct S6 a; 465/// a.e = BAR; 466/// } 467/// @endcode 468/// For the declaration of BAR, this routine will return a different 469/// scope. The scope S will be the scope of the unnamed enumeration 470/// within S6. In C++, this routine will return the scope associated 471/// with S6, because the enumeration's scope is a transparent 472/// context but structures can contain non-field names. In C, this 473/// routine will return the translation unit scope, since the 474/// enumeration's scope is a transparent context and structures cannot 475/// contain non-field names. 476Scope *Sema::getNonFieldDeclScope(Scope *S) { 477 while (((S->getFlags() & Scope::DeclScope) == 0) || 478 (S->getEntity() && 479 ((DeclContext *)S->getEntity())->isTransparentContext()) || 480 (S->isClassScope() && !getLangOptions().CPlusPlus)) 481 S = S->getParent(); 482 return S; 483} 484 485void Sema::InitBuiltinVaListType() { 486 if (!Context.getBuiltinVaListType().isNull()) 487 return; 488 489 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 490 NamedDecl *VaDecl = LookupSingleName(TUScope, VaIdent, LookupOrdinaryName); 491 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 492 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 493} 494 495/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 496/// file scope. lazily create a decl for it. ForRedeclaration is true 497/// if we're creating this built-in in anticipation of redeclaring the 498/// built-in. 499NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 500 Scope *S, bool ForRedeclaration, 501 SourceLocation Loc) { 502 Builtin::ID BID = (Builtin::ID)bid; 503 504 if (Context.BuiltinInfo.hasVAListUse(BID)) 505 InitBuiltinVaListType(); 506 507 ASTContext::GetBuiltinTypeError Error; 508 QualType R = Context.GetBuiltinType(BID, Error); 509 switch (Error) { 510 case ASTContext::GE_None: 511 // Okay 512 break; 513 514 case ASTContext::GE_Missing_stdio: 515 if (ForRedeclaration) 516 Diag(Loc, diag::err_implicit_decl_requires_stdio) 517 << Context.BuiltinInfo.GetName(BID); 518 return 0; 519 520 case ASTContext::GE_Missing_setjmp: 521 if (ForRedeclaration) 522 Diag(Loc, diag::err_implicit_decl_requires_setjmp) 523 << Context.BuiltinInfo.GetName(BID); 524 return 0; 525 } 526 527 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 528 Diag(Loc, diag::ext_implicit_lib_function_decl) 529 << Context.BuiltinInfo.GetName(BID) 530 << R; 531 if (Context.BuiltinInfo.getHeaderName(BID) && 532 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 533 != Diagnostic::Ignored) 534 Diag(Loc, diag::note_please_include_header) 535 << Context.BuiltinInfo.getHeaderName(BID) 536 << Context.BuiltinInfo.GetName(BID); 537 } 538 539 FunctionDecl *New = FunctionDecl::Create(Context, 540 Context.getTranslationUnitDecl(), 541 Loc, II, R, /*DInfo=*/0, 542 FunctionDecl::Extern, false, 543 /*hasPrototype=*/true); 544 New->setImplicit(); 545 546 // Create Decl objects for each parameter, adding them to the 547 // FunctionDecl. 548 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 549 llvm::SmallVector<ParmVarDecl*, 16> Params; 550 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 551 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 552 FT->getArgType(i), /*DInfo=*/0, 553 VarDecl::None, 0)); 554 New->setParams(Context, Params.data(), Params.size()); 555 } 556 557 AddKnownFunctionAttributes(New); 558 559 // TUScope is the translation-unit scope to insert this function into. 560 // FIXME: This is hideous. We need to teach PushOnScopeChains to 561 // relate Scopes to DeclContexts, and probably eliminate CurContext 562 // entirely, but we're not there yet. 563 DeclContext *SavedContext = CurContext; 564 CurContext = Context.getTranslationUnitDecl(); 565 PushOnScopeChains(New, TUScope); 566 CurContext = SavedContext; 567 return New; 568} 569 570/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 571/// same name and scope as a previous declaration 'Old'. Figure out 572/// how to resolve this situation, merging decls or emitting 573/// diagnostics as appropriate. If there was an error, set New to be invalid. 574/// 575void Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 576 // If either decl is known invalid already, set the new one to be invalid and 577 // don't bother doing any merging checks. 578 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 579 return New->setInvalidDecl(); 580 581 // Allow multiple definitions for ObjC built-in typedefs. 582 // FIXME: Verify the underlying types are equivalent! 583 if (getLangOptions().ObjC1) { 584 const IdentifierInfo *TypeID = New->getIdentifier(); 585 switch (TypeID->getLength()) { 586 default: break; 587 case 2: 588 if (!TypeID->isStr("id")) 589 break; 590 Context.ObjCIdRedefinitionType = New->getUnderlyingType(); 591 // Install the built-in type for 'id', ignoring the current definition. 592 New->setTypeForDecl(Context.getObjCIdType().getTypePtr()); 593 return; 594 case 5: 595 if (!TypeID->isStr("Class")) 596 break; 597 Context.ObjCClassRedefinitionType = New->getUnderlyingType(); 598 // Install the built-in type for 'Class', ignoring the current definition. 599 New->setTypeForDecl(Context.getObjCClassType().getTypePtr()); 600 return; 601 case 3: 602 if (!TypeID->isStr("SEL")) 603 break; 604 Context.setObjCSelType(Context.getTypeDeclType(New)); 605 return; 606 case 8: 607 if (!TypeID->isStr("Protocol")) 608 break; 609 Context.setObjCProtoType(New->getUnderlyingType()); 610 return; 611 } 612 // Fall through - the typedef name was not a builtin type. 613 } 614 // Verify the old decl was also a type. 615 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 616 if (!Old) { 617 Diag(New->getLocation(), diag::err_redefinition_different_kind) 618 << New->getDeclName(); 619 if (OldD->getLocation().isValid()) 620 Diag(OldD->getLocation(), diag::note_previous_definition); 621 return New->setInvalidDecl(); 622 } 623 624 // Determine the "old" type we'll use for checking and diagnostics. 625 QualType OldType; 626 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 627 OldType = OldTypedef->getUnderlyingType(); 628 else 629 OldType = Context.getTypeDeclType(Old); 630 631 // If the typedef types are not identical, reject them in all languages and 632 // with any extensions enabled. 633 634 if (OldType != New->getUnderlyingType() && 635 Context.getCanonicalType(OldType) != 636 Context.getCanonicalType(New->getUnderlyingType())) { 637 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 638 << New->getUnderlyingType() << OldType; 639 if (Old->getLocation().isValid()) 640 Diag(Old->getLocation(), diag::note_previous_definition); 641 return New->setInvalidDecl(); 642 } 643 644 if (getLangOptions().Microsoft) 645 return; 646 647 // C++ [dcl.typedef]p2: 648 // In a given non-class scope, a typedef specifier can be used to 649 // redefine the name of any type declared in that scope to refer 650 // to the type to which it already refers. 651 if (getLangOptions().CPlusPlus) { 652 if (!isa<CXXRecordDecl>(CurContext)) 653 return; 654 Diag(New->getLocation(), diag::err_redefinition) 655 << New->getDeclName(); 656 Diag(Old->getLocation(), diag::note_previous_definition); 657 return New->setInvalidDecl(); 658 } 659 660 // If we have a redefinition of a typedef in C, emit a warning. This warning 661 // is normally mapped to an error, but can be controlled with 662 // -Wtypedef-redefinition. If either the original or the redefinition is 663 // in a system header, don't emit this for compatibility with GCC. 664 if (PP.getDiagnostics().getSuppressSystemWarnings() && 665 (Context.getSourceManager().isInSystemHeader(Old->getLocation()) || 666 Context.getSourceManager().isInSystemHeader(New->getLocation()))) 667 return; 668 669 Diag(New->getLocation(), diag::warn_redefinition_of_typedef) 670 << New->getDeclName(); 671 Diag(Old->getLocation(), diag::note_previous_definition); 672 return; 673} 674 675/// DeclhasAttr - returns true if decl Declaration already has the target 676/// attribute. 677static bool 678DeclHasAttr(const Decl *decl, const Attr *target) { 679 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 680 if (attr->getKind() == target->getKind()) 681 return true; 682 683 return false; 684} 685 686/// MergeAttributes - append attributes from the Old decl to the New one. 687static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 688 for (const Attr *attr = Old->getAttrs(); attr; attr = attr->getNext()) { 689 if (!DeclHasAttr(New, attr) && attr->isMerged()) { 690 Attr *NewAttr = attr->clone(C); 691 NewAttr->setInherited(true); 692 New->addAttr(NewAttr); 693 } 694 } 695} 696 697/// Used in MergeFunctionDecl to keep track of function parameters in 698/// C. 699struct GNUCompatibleParamWarning { 700 ParmVarDecl *OldParm; 701 ParmVarDecl *NewParm; 702 QualType PromotedType; 703}; 704 705/// MergeFunctionDecl - We just parsed a function 'New' from 706/// declarator D which has the same name and scope as a previous 707/// declaration 'Old'. Figure out how to resolve this situation, 708/// merging decls or emitting diagnostics as appropriate. 709/// 710/// In C++, New and Old must be declarations that are not 711/// overloaded. Use IsOverload to determine whether New and Old are 712/// overloaded, and to select the Old declaration that New should be 713/// merged with. 714/// 715/// Returns true if there was an error, false otherwise. 716bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 717 assert(!isa<OverloadedFunctionDecl>(OldD) && 718 "Cannot merge with an overloaded function declaration"); 719 720 // Verify the old decl was also a function. 721 FunctionDecl *Old = 0; 722 if (FunctionTemplateDecl *OldFunctionTemplate 723 = dyn_cast<FunctionTemplateDecl>(OldD)) 724 Old = OldFunctionTemplate->getTemplatedDecl(); 725 else 726 Old = dyn_cast<FunctionDecl>(OldD); 727 if (!Old) { 728 Diag(New->getLocation(), diag::err_redefinition_different_kind) 729 << New->getDeclName(); 730 Diag(OldD->getLocation(), diag::note_previous_definition); 731 return true; 732 } 733 734 // Determine whether the previous declaration was a definition, 735 // implicit declaration, or a declaration. 736 diag::kind PrevDiag; 737 if (Old->isThisDeclarationADefinition()) 738 PrevDiag = diag::note_previous_definition; 739 else if (Old->isImplicit()) 740 PrevDiag = diag::note_previous_implicit_declaration; 741 else 742 PrevDiag = diag::note_previous_declaration; 743 744 QualType OldQType = Context.getCanonicalType(Old->getType()); 745 QualType NewQType = Context.getCanonicalType(New->getType()); 746 747 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 748 New->getStorageClass() == FunctionDecl::Static && 749 Old->getStorageClass() != FunctionDecl::Static) { 750 Diag(New->getLocation(), diag::err_static_non_static) 751 << New; 752 Diag(Old->getLocation(), PrevDiag); 753 return true; 754 } 755 756 if (getLangOptions().CPlusPlus) { 757 // (C++98 13.1p2): 758 // Certain function declarations cannot be overloaded: 759 // -- Function declarations that differ only in the return type 760 // cannot be overloaded. 761 QualType OldReturnType 762 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 763 QualType NewReturnType 764 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 765 if (OldReturnType != NewReturnType) { 766 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 767 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 768 return true; 769 } 770 771 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 772 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 773 if (OldMethod && NewMethod && !NewMethod->getFriendObjectKind() && 774 NewMethod->getLexicalDeclContext()->isRecord()) { 775 // -- Member function declarations with the same name and the 776 // same parameter types cannot be overloaded if any of them 777 // is a static member function declaration. 778 if (OldMethod->isStatic() || NewMethod->isStatic()) { 779 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 780 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 781 return true; 782 } 783 784 // C++ [class.mem]p1: 785 // [...] A member shall not be declared twice in the 786 // member-specification, except that a nested class or member 787 // class template can be declared and then later defined. 788 unsigned NewDiag; 789 if (isa<CXXConstructorDecl>(OldMethod)) 790 NewDiag = diag::err_constructor_redeclared; 791 else if (isa<CXXDestructorDecl>(NewMethod)) 792 NewDiag = diag::err_destructor_redeclared; 793 else if (isa<CXXConversionDecl>(NewMethod)) 794 NewDiag = diag::err_conv_function_redeclared; 795 else 796 NewDiag = diag::err_member_redeclared; 797 798 Diag(New->getLocation(), NewDiag); 799 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 800 } 801 802 // (C++98 8.3.5p3): 803 // All declarations for a function shall agree exactly in both the 804 // return type and the parameter-type-list. 805 if (OldQType == NewQType) 806 return MergeCompatibleFunctionDecls(New, Old); 807 808 // Fall through for conflicting redeclarations and redefinitions. 809 } 810 811 // C: Function types need to be compatible, not identical. This handles 812 // duplicate function decls like "void f(int); void f(enum X);" properly. 813 if (!getLangOptions().CPlusPlus && 814 Context.typesAreCompatible(OldQType, NewQType)) { 815 const FunctionType *OldFuncType = OldQType->getAs<FunctionType>(); 816 const FunctionType *NewFuncType = NewQType->getAs<FunctionType>(); 817 const FunctionProtoType *OldProto = 0; 818 if (isa<FunctionNoProtoType>(NewFuncType) && 819 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 820 // The old declaration provided a function prototype, but the 821 // new declaration does not. Merge in the prototype. 822 assert(!OldProto->hasExceptionSpec() && "Exception spec in C"); 823 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 824 OldProto->arg_type_end()); 825 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 826 ParamTypes.data(), ParamTypes.size(), 827 OldProto->isVariadic(), 828 OldProto->getTypeQuals()); 829 New->setType(NewQType); 830 New->setHasInheritedPrototype(); 831 832 // Synthesize a parameter for each argument type. 833 llvm::SmallVector<ParmVarDecl*, 16> Params; 834 for (FunctionProtoType::arg_type_iterator 835 ParamType = OldProto->arg_type_begin(), 836 ParamEnd = OldProto->arg_type_end(); 837 ParamType != ParamEnd; ++ParamType) { 838 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 839 SourceLocation(), 0, 840 *ParamType, /*DInfo=*/0, 841 VarDecl::None, 0); 842 Param->setImplicit(); 843 Params.push_back(Param); 844 } 845 846 New->setParams(Context, Params.data(), Params.size()); 847 } 848 849 return MergeCompatibleFunctionDecls(New, Old); 850 } 851 852 // GNU C permits a K&R definition to follow a prototype declaration 853 // if the declared types of the parameters in the K&R definition 854 // match the types in the prototype declaration, even when the 855 // promoted types of the parameters from the K&R definition differ 856 // from the types in the prototype. GCC then keeps the types from 857 // the prototype. 858 // 859 // If a variadic prototype is followed by a non-variadic K&R definition, 860 // the K&R definition becomes variadic. This is sort of an edge case, but 861 // it's legal per the standard depending on how you read C99 6.7.5.3p15 and 862 // C99 6.9.1p8. 863 if (!getLangOptions().CPlusPlus && 864 Old->hasPrototype() && !New->hasPrototype() && 865 New->getType()->getAs<FunctionProtoType>() && 866 Old->getNumParams() == New->getNumParams()) { 867 llvm::SmallVector<QualType, 16> ArgTypes; 868 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 869 const FunctionProtoType *OldProto 870 = Old->getType()->getAs<FunctionProtoType>(); 871 const FunctionProtoType *NewProto 872 = New->getType()->getAs<FunctionProtoType>(); 873 874 // Determine whether this is the GNU C extension. 875 QualType MergedReturn = Context.mergeTypes(OldProto->getResultType(), 876 NewProto->getResultType()); 877 bool LooseCompatible = !MergedReturn.isNull(); 878 for (unsigned Idx = 0, End = Old->getNumParams(); 879 LooseCompatible && Idx != End; ++Idx) { 880 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 881 ParmVarDecl *NewParm = New->getParamDecl(Idx); 882 if (Context.typesAreCompatible(OldParm->getType(), 883 NewProto->getArgType(Idx))) { 884 ArgTypes.push_back(NewParm->getType()); 885 } else if (Context.typesAreCompatible(OldParm->getType(), 886 NewParm->getType())) { 887 GNUCompatibleParamWarning Warn 888 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 889 Warnings.push_back(Warn); 890 ArgTypes.push_back(NewParm->getType()); 891 } else 892 LooseCompatible = false; 893 } 894 895 if (LooseCompatible) { 896 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 897 Diag(Warnings[Warn].NewParm->getLocation(), 898 diag::ext_param_promoted_not_compatible_with_prototype) 899 << Warnings[Warn].PromotedType 900 << Warnings[Warn].OldParm->getType(); 901 Diag(Warnings[Warn].OldParm->getLocation(), 902 diag::note_previous_declaration); 903 } 904 905 New->setType(Context.getFunctionType(MergedReturn, &ArgTypes[0], 906 ArgTypes.size(), 907 OldProto->isVariadic(), 0)); 908 return MergeCompatibleFunctionDecls(New, Old); 909 } 910 911 // Fall through to diagnose conflicting types. 912 } 913 914 // A function that has already been declared has been redeclared or defined 915 // with a different type- show appropriate diagnostic 916 if (unsigned BuiltinID = Old->getBuiltinID()) { 917 // The user has declared a builtin function with an incompatible 918 // signature. 919 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 920 // The function the user is redeclaring is a library-defined 921 // function like 'malloc' or 'printf'. Warn about the 922 // redeclaration, then pretend that we don't know about this 923 // library built-in. 924 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 925 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 926 << Old << Old->getType(); 927 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 928 Old->setInvalidDecl(); 929 return false; 930 } 931 932 PrevDiag = diag::note_previous_builtin_declaration; 933 } 934 935 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 936 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 937 return true; 938} 939 940/// \brief Completes the merge of two function declarations that are 941/// known to be compatible. 942/// 943/// This routine handles the merging of attributes and other 944/// properties of function declarations form the old declaration to 945/// the new declaration, once we know that New is in fact a 946/// redeclaration of Old. 947/// 948/// \returns false 949bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 950 // Merge the attributes 951 MergeAttributes(New, Old, Context); 952 953 // Merge the storage class. 954 if (Old->getStorageClass() != FunctionDecl::Extern && 955 Old->getStorageClass() != FunctionDecl::None) 956 New->setStorageClass(Old->getStorageClass()); 957 958 // Merge "pure" flag. 959 if (Old->isPure()) 960 New->setPure(); 961 962 // Merge the "deleted" flag. 963 if (Old->isDeleted()) 964 New->setDeleted(); 965 966 if (getLangOptions().CPlusPlus) 967 return MergeCXXFunctionDecl(New, Old); 968 969 return false; 970} 971 972/// MergeVarDecl - We just parsed a variable 'New' which has the same name 973/// and scope as a previous declaration 'Old'. Figure out how to resolve this 974/// situation, merging decls or emitting diagnostics as appropriate. 975/// 976/// Tentative definition rules (C99 6.9.2p2) are checked by 977/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 978/// definitions here, since the initializer hasn't been attached. 979/// 980void Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 981 // If either decl is invalid, make sure the new one is marked invalid and 982 // don't do any other checking. 983 if (New->isInvalidDecl() || OldD->isInvalidDecl()) 984 return New->setInvalidDecl(); 985 986 // Verify the old decl was also a variable. 987 VarDecl *Old = dyn_cast<VarDecl>(OldD); 988 if (!Old) { 989 Diag(New->getLocation(), diag::err_redefinition_different_kind) 990 << New->getDeclName(); 991 Diag(OldD->getLocation(), diag::note_previous_definition); 992 return New->setInvalidDecl(); 993 } 994 995 MergeAttributes(New, Old, Context); 996 997 // Merge the types 998 QualType MergedT; 999 if (getLangOptions().CPlusPlus) { 1000 if (Context.hasSameType(New->getType(), Old->getType())) 1001 MergedT = New->getType(); 1002 // C++ [basic.types]p7: 1003 // [...] The declared type of an array object might be an array of 1004 // unknown size and therefore be incomplete at one point in a 1005 // translation unit and complete later on; [...] 1006 else if (Old->getType()->isIncompleteArrayType() && 1007 New->getType()->isArrayType()) { 1008 CanQual<ArrayType> OldArray 1009 = Context.getCanonicalType(Old->getType())->getAs<ArrayType>(); 1010 CanQual<ArrayType> NewArray 1011 = Context.getCanonicalType(New->getType())->getAs<ArrayType>(); 1012 if (OldArray->getElementType() == NewArray->getElementType()) 1013 MergedT = New->getType(); 1014 } 1015 } else { 1016 MergedT = Context.mergeTypes(New->getType(), Old->getType()); 1017 } 1018 if (MergedT.isNull()) { 1019 Diag(New->getLocation(), diag::err_redefinition_different_type) 1020 << New->getDeclName(); 1021 Diag(Old->getLocation(), diag::note_previous_definition); 1022 return New->setInvalidDecl(); 1023 } 1024 New->setType(MergedT); 1025 1026 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 1027 if (New->getStorageClass() == VarDecl::Static && 1028 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 1029 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 1030 Diag(Old->getLocation(), diag::note_previous_definition); 1031 return New->setInvalidDecl(); 1032 } 1033 // C99 6.2.2p4: 1034 // For an identifier declared with the storage-class specifier 1035 // extern in a scope in which a prior declaration of that 1036 // identifier is visible,23) if the prior declaration specifies 1037 // internal or external linkage, the linkage of the identifier at 1038 // the later declaration is the same as the linkage specified at 1039 // the prior declaration. If no prior declaration is visible, or 1040 // if the prior declaration specifies no linkage, then the 1041 // identifier has external linkage. 1042 if (New->hasExternalStorage() && Old->hasLinkage()) 1043 /* Okay */; 1044 else if (New->getStorageClass() != VarDecl::Static && 1045 Old->getStorageClass() == VarDecl::Static) { 1046 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 1047 Diag(Old->getLocation(), diag::note_previous_definition); 1048 return New->setInvalidDecl(); 1049 } 1050 1051 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 1052 1053 // FIXME: The test for external storage here seems wrong? We still 1054 // need to check for mismatches. 1055 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 1056 // Don't complain about out-of-line definitions of static members. 1057 !(Old->getLexicalDeclContext()->isRecord() && 1058 !New->getLexicalDeclContext()->isRecord())) { 1059 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 1060 Diag(Old->getLocation(), diag::note_previous_definition); 1061 return New->setInvalidDecl(); 1062 } 1063 1064 if (New->isThreadSpecified() && !Old->isThreadSpecified()) { 1065 Diag(New->getLocation(), diag::err_thread_non_thread) << New->getDeclName(); 1066 Diag(Old->getLocation(), diag::note_previous_definition); 1067 } else if (!New->isThreadSpecified() && Old->isThreadSpecified()) { 1068 Diag(New->getLocation(), diag::err_non_thread_thread) << New->getDeclName(); 1069 Diag(Old->getLocation(), diag::note_previous_definition); 1070 } 1071 1072 // Keep a chain of previous declarations. 1073 New->setPreviousDeclaration(Old); 1074} 1075 1076/// CheckFallThrough - Check that we don't fall off the end of a 1077/// Statement that should return a value. 1078/// 1079/// \returns AlwaysFallThrough iff we always fall off the end of the statement, 1080/// MaybeFallThrough iff we might or might not fall off the end, 1081/// NeverFallThroughOrReturn iff we never fall off the end of the statement or 1082/// return. We assume NeverFallThrough iff we never fall off the end of the 1083/// statement but we may return. We assume that functions not marked noreturn 1084/// will return. 1085Sema::ControlFlowKind Sema::CheckFallThrough(Stmt *Root) { 1086 // FIXME: Eventually share this CFG object when we have other warnings based 1087 // of the CFG. This can be done using AnalysisContext. 1088 llvm::OwningPtr<CFG> cfg (CFG::buildCFG(Root, &Context)); 1089 1090 // FIXME: They should never return 0, fix that, delete this code. 1091 if (cfg == 0) 1092 // FIXME: This should be NeverFallThrough 1093 return NeverFallThroughOrReturn; 1094 // The CFG leaves in dead things, and we don't want to dead code paths to 1095 // confuse us, so we mark all live things first. 1096 std::queue<CFGBlock*> workq; 1097 llvm::BitVector live(cfg->getNumBlockIDs()); 1098 // Prep work queue 1099 workq.push(&cfg->getEntry()); 1100 // Solve 1101 while (!workq.empty()) { 1102 CFGBlock *item = workq.front(); 1103 workq.pop(); 1104 live.set(item->getBlockID()); 1105 for (CFGBlock::succ_iterator I=item->succ_begin(), 1106 E=item->succ_end(); 1107 I != E; 1108 ++I) { 1109 if ((*I) && !live[(*I)->getBlockID()]) { 1110 live.set((*I)->getBlockID()); 1111 workq.push(*I); 1112 } 1113 } 1114 } 1115 1116 // Now we know what is live, we check the live precessors of the exit block 1117 // and look for fall through paths, being careful to ignore normal returns, 1118 // and exceptional paths. 1119 bool HasLiveReturn = false; 1120 bool HasFakeEdge = false; 1121 bool HasPlainEdge = false; 1122 for (CFGBlock::pred_iterator I=cfg->getExit().pred_begin(), 1123 E = cfg->getExit().pred_end(); 1124 I != E; 1125 ++I) { 1126 CFGBlock& B = **I; 1127 if (!live[B.getBlockID()]) 1128 continue; 1129 if (B.size() == 0) { 1130 // A labeled empty statement, or the entry block... 1131 HasPlainEdge = true; 1132 continue; 1133 } 1134 Stmt *S = B[B.size()-1]; 1135 if (isa<ReturnStmt>(S)) { 1136 HasLiveReturn = true; 1137 continue; 1138 } 1139 if (isa<ObjCAtThrowStmt>(S)) { 1140 HasFakeEdge = true; 1141 continue; 1142 } 1143 if (isa<CXXThrowExpr>(S)) { 1144 HasFakeEdge = true; 1145 continue; 1146 } 1147 bool NoReturnEdge = false; 1148 if (CallExpr *C = dyn_cast<CallExpr>(S)) { 1149 Expr *CEE = C->getCallee()->IgnoreParenCasts(); 1150 if (CEE->getType().getNoReturnAttr()) { 1151 NoReturnEdge = true; 1152 HasFakeEdge = true; 1153 } else if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(CEE)) { 1154 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(DRE->getDecl())) { 1155 if (FD->hasAttr<NoReturnAttr>()) { 1156 NoReturnEdge = true; 1157 HasFakeEdge = true; 1158 } 1159 } 1160 } 1161 } 1162 // FIXME: Add noreturn message sends. 1163 if (NoReturnEdge == false) 1164 HasPlainEdge = true; 1165 } 1166 if (!HasPlainEdge) { 1167 if (HasLiveReturn) 1168 return NeverFallThrough; 1169 return NeverFallThroughOrReturn; 1170 } 1171 if (HasFakeEdge || HasLiveReturn) 1172 return MaybeFallThrough; 1173 // This says AlwaysFallThrough for calls to functions that are not marked 1174 // noreturn, that don't return. If people would like this warning to be more 1175 // accurate, such functions should be marked as noreturn. 1176 return AlwaysFallThrough; 1177} 1178 1179/// CheckFallThroughForFunctionDef - Check that we don't fall off the end of a 1180/// function that should return a value. Check that we don't fall off the end 1181/// of a noreturn function. We assume that functions and blocks not marked 1182/// noreturn will return. 1183void Sema::CheckFallThroughForFunctionDef(Decl *D, Stmt *Body) { 1184 // FIXME: Would be nice if we had a better way to control cascading errors, 1185 // but for now, avoid them. The problem is that when Parse sees: 1186 // int foo() { return a; } 1187 // The return is eaten and the Sema code sees just: 1188 // int foo() { } 1189 // which this code would then warn about. 1190 if (getDiagnostics().hasErrorOccurred()) 1191 return; 1192 1193 bool ReturnsVoid = false; 1194 bool HasNoReturn = false; 1195 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 1196 // If the result type of the function is a dependent type, we don't know 1197 // whether it will be void or not, so don't 1198 if (FD->getResultType()->isDependentType()) 1199 return; 1200 if (FD->getResultType()->isVoidType()) 1201 ReturnsVoid = true; 1202 if (FD->hasAttr<NoReturnAttr>()) 1203 HasNoReturn = true; 1204 } else if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) { 1205 if (MD->getResultType()->isVoidType()) 1206 ReturnsVoid = true; 1207 if (MD->hasAttr<NoReturnAttr>()) 1208 HasNoReturn = true; 1209 } 1210 1211 // Short circuit for compilation speed. 1212 if ((Diags.getDiagnosticLevel(diag::warn_maybe_falloff_nonvoid_function) 1213 == Diagnostic::Ignored || ReturnsVoid) 1214 && (Diags.getDiagnosticLevel(diag::warn_noreturn_function_has_return_expr) 1215 == Diagnostic::Ignored || !HasNoReturn) 1216 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1217 == Diagnostic::Ignored || !ReturnsVoid)) 1218 return; 1219 // FIXME: Function try block 1220 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1221 switch (CheckFallThrough(Body)) { 1222 case MaybeFallThrough: 1223 if (HasNoReturn) 1224 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1225 else if (!ReturnsVoid) 1226 Diag(Compound->getRBracLoc(),diag::warn_maybe_falloff_nonvoid_function); 1227 break; 1228 case AlwaysFallThrough: 1229 if (HasNoReturn) 1230 Diag(Compound->getRBracLoc(), diag::warn_falloff_noreturn_function); 1231 else if (!ReturnsVoid) 1232 Diag(Compound->getRBracLoc(), diag::warn_falloff_nonvoid_function); 1233 break; 1234 case NeverFallThroughOrReturn: 1235 if (ReturnsVoid && !HasNoReturn) 1236 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_function); 1237 break; 1238 case NeverFallThrough: 1239 break; 1240 } 1241 } 1242} 1243 1244/// CheckFallThroughForBlock - Check that we don't fall off the end of a block 1245/// that should return a value. Check that we don't fall off the end of a 1246/// noreturn block. We assume that functions and blocks not marked noreturn 1247/// will return. 1248void Sema::CheckFallThroughForBlock(QualType BlockTy, Stmt *Body) { 1249 // FIXME: Would be nice if we had a better way to control cascading errors, 1250 // but for now, avoid them. The problem is that when Parse sees: 1251 // int foo() { return a; } 1252 // The return is eaten and the Sema code sees just: 1253 // int foo() { } 1254 // which this code would then warn about. 1255 if (getDiagnostics().hasErrorOccurred()) 1256 return; 1257 bool ReturnsVoid = false; 1258 bool HasNoReturn = false; 1259 if (const FunctionType *FT =BlockTy->getPointeeType()->getAs<FunctionType>()){ 1260 if (FT->getResultType()->isVoidType()) 1261 ReturnsVoid = true; 1262 if (FT->getNoReturnAttr()) 1263 HasNoReturn = true; 1264 } 1265 1266 // Short circuit for compilation speed. 1267 if (ReturnsVoid 1268 && !HasNoReturn 1269 && (Diags.getDiagnosticLevel(diag::warn_suggest_noreturn_block) 1270 == Diagnostic::Ignored || !ReturnsVoid)) 1271 return; 1272 // FIXME: Funtion try block 1273 if (CompoundStmt *Compound = dyn_cast<CompoundStmt>(Body)) { 1274 switch (CheckFallThrough(Body)) { 1275 case MaybeFallThrough: 1276 if (HasNoReturn) 1277 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1278 else if (!ReturnsVoid) 1279 Diag(Compound->getRBracLoc(), diag::err_maybe_falloff_nonvoid_block); 1280 break; 1281 case AlwaysFallThrough: 1282 if (HasNoReturn) 1283 Diag(Compound->getRBracLoc(), diag::err_noreturn_block_has_return_expr); 1284 else if (!ReturnsVoid) 1285 Diag(Compound->getRBracLoc(), diag::err_falloff_nonvoid_block); 1286 break; 1287 case NeverFallThroughOrReturn: 1288 if (ReturnsVoid) 1289 Diag(Compound->getLBracLoc(), diag::warn_suggest_noreturn_block); 1290 break; 1291 case NeverFallThrough: 1292 break; 1293 } 1294 } 1295} 1296 1297/// CheckParmsForFunctionDef - Check that the parameters of the given 1298/// function are appropriate for the definition of a function. This 1299/// takes care of any checks that cannot be performed on the 1300/// declaration itself, e.g., that the types of each of the function 1301/// parameters are complete. 1302bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 1303 bool HasInvalidParm = false; 1304 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 1305 ParmVarDecl *Param = FD->getParamDecl(p); 1306 1307 // C99 6.7.5.3p4: the parameters in a parameter type list in a 1308 // function declarator that is part of a function definition of 1309 // that function shall not have incomplete type. 1310 // 1311 // This is also C++ [dcl.fct]p6. 1312 if (!Param->isInvalidDecl() && 1313 RequireCompleteType(Param->getLocation(), Param->getType(), 1314 diag::err_typecheck_decl_incomplete_type)) { 1315 Param->setInvalidDecl(); 1316 HasInvalidParm = true; 1317 } 1318 1319 // C99 6.9.1p5: If the declarator includes a parameter type list, the 1320 // declaration of each parameter shall include an identifier. 1321 if (Param->getIdentifier() == 0 && 1322 !Param->isImplicit() && 1323 !getLangOptions().CPlusPlus) 1324 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 1325 } 1326 1327 return HasInvalidParm; 1328} 1329 1330/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 1331/// no declarator (e.g. "struct foo;") is parsed. 1332Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 1333 // FIXME: Error on auto/register at file scope 1334 // FIXME: Error on inline/virtual/explicit 1335 // FIXME: Error on invalid restrict 1336 // FIXME: Warn on useless __thread 1337 // FIXME: Warn on useless const/volatile 1338 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 1339 // FIXME: Warn on useless attributes 1340 Decl *TagD = 0; 1341 TagDecl *Tag = 0; 1342 if (DS.getTypeSpecType() == DeclSpec::TST_class || 1343 DS.getTypeSpecType() == DeclSpec::TST_struct || 1344 DS.getTypeSpecType() == DeclSpec::TST_union || 1345 DS.getTypeSpecType() == DeclSpec::TST_enum) { 1346 TagD = static_cast<Decl *>(DS.getTypeRep()); 1347 1348 if (!TagD) // We probably had an error 1349 return DeclPtrTy(); 1350 1351 // Note that the above type specs guarantee that the 1352 // type rep is a Decl, whereas in many of the others 1353 // it's a Type. 1354 Tag = dyn_cast<TagDecl>(TagD); 1355 } 1356 1357 if (DS.isFriendSpecified()) { 1358 // If we're dealing with a class template decl, assume that the 1359 // template routines are handling it. 1360 if (TagD && isa<ClassTemplateDecl>(TagD)) 1361 return DeclPtrTy(); 1362 return ActOnFriendTypeDecl(S, DS, MultiTemplateParamsArg(*this, 0, 0)); 1363 } 1364 1365 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 1366 // If there are attributes in the DeclSpec, apply them to the record. 1367 if (const AttributeList *AL = DS.getAttributes()) 1368 ProcessDeclAttributeList(S, Record, AL); 1369 1370 if (!Record->getDeclName() && Record->isDefinition() && 1371 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 1372 if (getLangOptions().CPlusPlus || 1373 Record->getDeclContext()->isRecord()) 1374 return BuildAnonymousStructOrUnion(S, DS, Record); 1375 1376 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1377 << DS.getSourceRange(); 1378 } 1379 1380 // Microsoft allows unnamed struct/union fields. Don't complain 1381 // about them. 1382 // FIXME: Should we support Microsoft's extensions in this area? 1383 if (Record->getDeclName() && getLangOptions().Microsoft) 1384 return DeclPtrTy::make(Tag); 1385 } 1386 1387 if (!DS.isMissingDeclaratorOk() && 1388 DS.getTypeSpecType() != DeclSpec::TST_error) { 1389 // Warn about typedefs of enums without names, since this is an 1390 // extension in both Microsoft an GNU. 1391 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1392 Tag && isa<EnumDecl>(Tag)) { 1393 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1394 << DS.getSourceRange(); 1395 return DeclPtrTy::make(Tag); 1396 } 1397 1398 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1399 << DS.getSourceRange(); 1400 return DeclPtrTy(); 1401 } 1402 1403 return DeclPtrTy::make(Tag); 1404} 1405 1406/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1407/// anonymous struct or union AnonRecord into the owning context Owner 1408/// and scope S. This routine will be invoked just after we realize 1409/// that an unnamed union or struct is actually an anonymous union or 1410/// struct, e.g., 1411/// 1412/// @code 1413/// union { 1414/// int i; 1415/// float f; 1416/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1417/// // f into the surrounding scope.x 1418/// @endcode 1419/// 1420/// This routine is recursive, injecting the names of nested anonymous 1421/// structs/unions into the owning context and scope as well. 1422bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1423 RecordDecl *AnonRecord) { 1424 bool Invalid = false; 1425 for (RecordDecl::field_iterator F = AnonRecord->field_begin(), 1426 FEnd = AnonRecord->field_end(); 1427 F != FEnd; ++F) { 1428 if ((*F)->getDeclName()) { 1429 LookupResult R(*this, (*F)->getDeclName(), SourceLocation(), 1430 LookupOrdinaryName, ForRedeclaration); 1431 LookupQualifiedName(R, Owner); 1432 NamedDecl *PrevDecl = R.getAsSingleDecl(Context); 1433 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1434 // C++ [class.union]p2: 1435 // The names of the members of an anonymous union shall be 1436 // distinct from the names of any other entity in the 1437 // scope in which the anonymous union is declared. 1438 unsigned diagKind 1439 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1440 : diag::err_anonymous_struct_member_redecl; 1441 Diag((*F)->getLocation(), diagKind) 1442 << (*F)->getDeclName(); 1443 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1444 Invalid = true; 1445 } else { 1446 // C++ [class.union]p2: 1447 // For the purpose of name lookup, after the anonymous union 1448 // definition, the members of the anonymous union are 1449 // considered to have been defined in the scope in which the 1450 // anonymous union is declared. 1451 Owner->makeDeclVisibleInContext(*F); 1452 S->AddDecl(DeclPtrTy::make(*F)); 1453 IdResolver.AddDecl(*F); 1454 } 1455 } else if (const RecordType *InnerRecordType 1456 = (*F)->getType()->getAs<RecordType>()) { 1457 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1458 if (InnerRecord->isAnonymousStructOrUnion()) 1459 Invalid = Invalid || 1460 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1461 } 1462 } 1463 1464 return Invalid; 1465} 1466 1467/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1468/// anonymous structure or union. Anonymous unions are a C++ feature 1469/// (C++ [class.union]) and a GNU C extension; anonymous structures 1470/// are a GNU C and GNU C++ extension. 1471Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1472 RecordDecl *Record) { 1473 DeclContext *Owner = Record->getDeclContext(); 1474 1475 // Diagnose whether this anonymous struct/union is an extension. 1476 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1477 Diag(Record->getLocation(), diag::ext_anonymous_union); 1478 else if (!Record->isUnion()) 1479 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1480 1481 // C and C++ require different kinds of checks for anonymous 1482 // structs/unions. 1483 bool Invalid = false; 1484 if (getLangOptions().CPlusPlus) { 1485 const char* PrevSpec = 0; 1486 unsigned DiagID; 1487 // C++ [class.union]p3: 1488 // Anonymous unions declared in a named namespace or in the 1489 // global namespace shall be declared static. 1490 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1491 (isa<TranslationUnitDecl>(Owner) || 1492 (isa<NamespaceDecl>(Owner) && 1493 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1494 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1495 Invalid = true; 1496 1497 // Recover by adding 'static'. 1498 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), 1499 PrevSpec, DiagID); 1500 } 1501 // C++ [class.union]p3: 1502 // A storage class is not allowed in a declaration of an 1503 // anonymous union in a class scope. 1504 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1505 isa<RecordDecl>(Owner)) { 1506 Diag(DS.getStorageClassSpecLoc(), 1507 diag::err_anonymous_union_with_storage_spec); 1508 Invalid = true; 1509 1510 // Recover by removing the storage specifier. 1511 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1512 PrevSpec, DiagID); 1513 } 1514 1515 // C++ [class.union]p2: 1516 // The member-specification of an anonymous union shall only 1517 // define non-static data members. [Note: nested types and 1518 // functions cannot be declared within an anonymous union. ] 1519 for (DeclContext::decl_iterator Mem = Record->decls_begin(), 1520 MemEnd = Record->decls_end(); 1521 Mem != MemEnd; ++Mem) { 1522 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1523 // C++ [class.union]p3: 1524 // An anonymous union shall not have private or protected 1525 // members (clause 11). 1526 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1527 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1528 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1529 Invalid = true; 1530 } 1531 } else if ((*Mem)->isImplicit()) { 1532 // Any implicit members are fine. 1533 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1534 // This is a type that showed up in an 1535 // elaborated-type-specifier inside the anonymous struct or 1536 // union, but which actually declares a type outside of the 1537 // anonymous struct or union. It's okay. 1538 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1539 if (!MemRecord->isAnonymousStructOrUnion() && 1540 MemRecord->getDeclName()) { 1541 // This is a nested type declaration. 1542 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1543 << (int)Record->isUnion(); 1544 Invalid = true; 1545 } 1546 } else { 1547 // We have something that isn't a non-static data 1548 // member. Complain about it. 1549 unsigned DK = diag::err_anonymous_record_bad_member; 1550 if (isa<TypeDecl>(*Mem)) 1551 DK = diag::err_anonymous_record_with_type; 1552 else if (isa<FunctionDecl>(*Mem)) 1553 DK = diag::err_anonymous_record_with_function; 1554 else if (isa<VarDecl>(*Mem)) 1555 DK = diag::err_anonymous_record_with_static; 1556 Diag((*Mem)->getLocation(), DK) 1557 << (int)Record->isUnion(); 1558 Invalid = true; 1559 } 1560 } 1561 } 1562 1563 if (!Record->isUnion() && !Owner->isRecord()) { 1564 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1565 << (int)getLangOptions().CPlusPlus; 1566 Invalid = true; 1567 } 1568 1569 // Mock up a declarator. 1570 Declarator Dc(DS, Declarator::TypeNameContext); 1571 DeclaratorInfo *DInfo = 0; 1572 GetTypeForDeclarator(Dc, S, &DInfo); 1573 assert(DInfo && "couldn't build declarator info for anonymous struct/union"); 1574 1575 // Create a declaration for this anonymous struct/union. 1576 NamedDecl *Anon = 0; 1577 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1578 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1579 /*IdentifierInfo=*/0, 1580 Context.getTypeDeclType(Record), 1581 DInfo, 1582 /*BitWidth=*/0, /*Mutable=*/false); 1583 Anon->setAccess(AS_public); 1584 if (getLangOptions().CPlusPlus) 1585 FieldCollector->Add(cast<FieldDecl>(Anon)); 1586 } else { 1587 VarDecl::StorageClass SC; 1588 switch (DS.getStorageClassSpec()) { 1589 default: assert(0 && "Unknown storage class!"); 1590 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1591 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1592 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1593 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1594 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1595 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1596 case DeclSpec::SCS_mutable: 1597 // mutable can only appear on non-static class members, so it's always 1598 // an error here 1599 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1600 Invalid = true; 1601 SC = VarDecl::None; 1602 break; 1603 } 1604 1605 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1606 /*IdentifierInfo=*/0, 1607 Context.getTypeDeclType(Record), 1608 DInfo, 1609 SC); 1610 } 1611 Anon->setImplicit(); 1612 1613 // Add the anonymous struct/union object to the current 1614 // context. We'll be referencing this object when we refer to one of 1615 // its members. 1616 Owner->addDecl(Anon); 1617 1618 // Inject the members of the anonymous struct/union into the owning 1619 // context and into the identifier resolver chain for name lookup 1620 // purposes. 1621 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1622 Invalid = true; 1623 1624 // Mark this as an anonymous struct/union type. Note that we do not 1625 // do this until after we have already checked and injected the 1626 // members of this anonymous struct/union type, because otherwise 1627 // the members could be injected twice: once by DeclContext when it 1628 // builds its lookup table, and once by 1629 // InjectAnonymousStructOrUnionMembers. 1630 Record->setAnonymousStructOrUnion(true); 1631 1632 if (Invalid) 1633 Anon->setInvalidDecl(); 1634 1635 return DeclPtrTy::make(Anon); 1636} 1637 1638 1639/// GetNameForDeclarator - Determine the full declaration name for the 1640/// given Declarator. 1641DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1642 return GetNameFromUnqualifiedId(D.getName()); 1643} 1644 1645/// \brief Retrieves the canonicalized name from a parsed unqualified-id. 1646DeclarationName Sema::GetNameFromUnqualifiedId(UnqualifiedId &Name) { 1647 switch (Name.getKind()) { 1648 case UnqualifiedId::IK_Identifier: 1649 return DeclarationName(Name.Identifier); 1650 1651 case UnqualifiedId::IK_OperatorFunctionId: 1652 return Context.DeclarationNames.getCXXOperatorName( 1653 Name.OperatorFunctionId.Operator); 1654 1655 case UnqualifiedId::IK_ConversionFunctionId: { 1656 QualType Ty = GetTypeFromParser(Name.ConversionFunctionId); 1657 if (Ty.isNull()) 1658 return DeclarationName(); 1659 1660 return Context.DeclarationNames.getCXXConversionFunctionName( 1661 Context.getCanonicalType(Ty)); 1662 } 1663 1664 case UnqualifiedId::IK_ConstructorName: { 1665 QualType Ty = GetTypeFromParser(Name.ConstructorName); 1666 if (Ty.isNull()) 1667 return DeclarationName(); 1668 1669 return Context.DeclarationNames.getCXXConstructorName( 1670 Context.getCanonicalType(Ty)); 1671 } 1672 1673 case UnqualifiedId::IK_DestructorName: { 1674 QualType Ty = GetTypeFromParser(Name.DestructorName); 1675 if (Ty.isNull()) 1676 return DeclarationName(); 1677 1678 return Context.DeclarationNames.getCXXDestructorName( 1679 Context.getCanonicalType(Ty)); 1680 } 1681 1682 case UnqualifiedId::IK_TemplateId: { 1683 TemplateName TName 1684 = TemplateName::getFromVoidPointer(Name.TemplateId->Template); 1685 if (TemplateDecl *Template = TName.getAsTemplateDecl()) 1686 return Template->getDeclName(); 1687 if (OverloadedFunctionDecl *Ovl = TName.getAsOverloadedFunctionDecl()) 1688 return Ovl->getDeclName(); 1689 1690 return DeclarationName(); 1691 } 1692 } 1693 1694 assert(false && "Unknown name kind"); 1695 return DeclarationName(); 1696} 1697 1698/// isNearlyMatchingFunction - Determine whether the C++ functions 1699/// Declaration and Definition are "nearly" matching. This heuristic 1700/// is used to improve diagnostics in the case where an out-of-line 1701/// function definition doesn't match any declaration within 1702/// the class or namespace. 1703static bool isNearlyMatchingFunction(ASTContext &Context, 1704 FunctionDecl *Declaration, 1705 FunctionDecl *Definition) { 1706 if (Declaration->param_size() != Definition->param_size()) 1707 return false; 1708 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1709 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1710 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1711 1712 if (!Context.hasSameUnqualifiedType(DeclParamTy.getNonReferenceType(), 1713 DefParamTy.getNonReferenceType())) 1714 return false; 1715 } 1716 1717 return true; 1718} 1719 1720Sema::DeclPtrTy 1721Sema::HandleDeclarator(Scope *S, Declarator &D, 1722 MultiTemplateParamsArg TemplateParamLists, 1723 bool IsFunctionDefinition) { 1724 DeclarationName Name = GetNameForDeclarator(D); 1725 1726 // All of these full declarators require an identifier. If it doesn't have 1727 // one, the ParsedFreeStandingDeclSpec action should be used. 1728 if (!Name) { 1729 if (!D.isInvalidType()) // Reject this if we think it is valid. 1730 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1731 diag::err_declarator_need_ident) 1732 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1733 return DeclPtrTy(); 1734 } 1735 1736 // The scope passed in may not be a decl scope. Zip up the scope tree until 1737 // we find one that is. 1738 while ((S->getFlags() & Scope::DeclScope) == 0 || 1739 (S->getFlags() & Scope::TemplateParamScope) != 0) 1740 S = S->getParent(); 1741 1742 // If this is an out-of-line definition of a member of a class template 1743 // or class template partial specialization, we may need to rebuild the 1744 // type specifier in the declarator. See RebuildTypeInCurrentInstantiation() 1745 // for more information. 1746 // FIXME: cope with decltype(expr) and typeof(expr) once the rebuilder can 1747 // handle expressions properly. 1748 DeclSpec &DS = const_cast<DeclSpec&>(D.getDeclSpec()); 1749 if (D.getCXXScopeSpec().isSet() && !D.getCXXScopeSpec().isInvalid() && 1750 isDependentScopeSpecifier(D.getCXXScopeSpec()) && 1751 (DS.getTypeSpecType() == DeclSpec::TST_typename || 1752 DS.getTypeSpecType() == DeclSpec::TST_typeofType || 1753 DS.getTypeSpecType() == DeclSpec::TST_typeofExpr || 1754 DS.getTypeSpecType() == DeclSpec::TST_decltype)) { 1755 if (DeclContext *DC = computeDeclContext(D.getCXXScopeSpec(), true)) { 1756 // FIXME: Preserve type source info. 1757 QualType T = GetTypeFromParser(DS.getTypeRep()); 1758 EnterDeclaratorContext(S, DC); 1759 T = RebuildTypeInCurrentInstantiation(T, D.getIdentifierLoc(), Name); 1760 ExitDeclaratorContext(S); 1761 if (T.isNull()) 1762 return DeclPtrTy(); 1763 DS.UpdateTypeRep(T.getAsOpaquePtr()); 1764 } 1765 } 1766 1767 DeclContext *DC; 1768 NamedDecl *PrevDecl; 1769 NamedDecl *New; 1770 1771 DeclaratorInfo *DInfo = 0; 1772 QualType R = GetTypeForDeclarator(D, S, &DInfo); 1773 1774 // See if this is a redefinition of a variable in the same scope. 1775 if (D.getCXXScopeSpec().isInvalid()) { 1776 DC = CurContext; 1777 PrevDecl = 0; 1778 D.setInvalidType(); 1779 } else if (!D.getCXXScopeSpec().isSet()) { 1780 LookupNameKind NameKind = LookupOrdinaryName; 1781 1782 // If the declaration we're planning to build will be a function 1783 // or object with linkage, then look for another declaration with 1784 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1785 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1786 /* Do nothing*/; 1787 else if (R->isFunctionType()) { 1788 if (CurContext->isFunctionOrMethod() || 1789 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1790 NameKind = LookupRedeclarationWithLinkage; 1791 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1792 NameKind = LookupRedeclarationWithLinkage; 1793 else if (CurContext->getLookupContext()->isTranslationUnit() && 1794 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_static) 1795 NameKind = LookupRedeclarationWithLinkage; 1796 1797 DC = CurContext; 1798 LookupResult R(*this, Name, D.getIdentifierLoc(), NameKind, 1799 ForRedeclaration); 1800 1801 LookupName(R, S, NameKind == LookupRedeclarationWithLinkage); 1802 PrevDecl = R.getAsSingleDecl(Context); 1803 } else { // Something like "int foo::x;" 1804 DC = computeDeclContext(D.getCXXScopeSpec(), true); 1805 1806 if (!DC) { 1807 // If we could not compute the declaration context, it's because the 1808 // declaration context is dependent but does not refer to a class, 1809 // class template, or class template partial specialization. Complain 1810 // and return early, to avoid the coming semantic disaster. 1811 Diag(D.getIdentifierLoc(), 1812 diag::err_template_qualified_declarator_no_match) 1813 << (NestedNameSpecifier*)D.getCXXScopeSpec().getScopeRep() 1814 << D.getCXXScopeSpec().getRange(); 1815 return DeclPtrTy(); 1816 } 1817 1818 if (!DC->isDependentContext() && 1819 RequireCompleteDeclContext(D.getCXXScopeSpec())) 1820 return DeclPtrTy(); 1821 1822 LookupResult Res(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 1823 ForRedeclaration); 1824 LookupQualifiedName(Res, DC); 1825 PrevDecl = Res.getAsSingleDecl(Context); 1826 1827 // C++ 7.3.1.2p2: 1828 // Members (including explicit specializations of templates) of a named 1829 // namespace can also be defined outside that namespace by explicit 1830 // qualification of the name being defined, provided that the entity being 1831 // defined was already declared in the namespace and the definition appears 1832 // after the point of declaration in a namespace that encloses the 1833 // declarations namespace. 1834 // 1835 // Note that we only check the context at this point. We don't yet 1836 // have enough information to make sure that PrevDecl is actually 1837 // the declaration we want to match. For example, given: 1838 // 1839 // class X { 1840 // void f(); 1841 // void f(float); 1842 // }; 1843 // 1844 // void X::f(int) { } // ill-formed 1845 // 1846 // In this case, PrevDecl will point to the overload set 1847 // containing the two f's declared in X, but neither of them 1848 // matches. 1849 1850 // First check whether we named the global scope. 1851 if (isa<TranslationUnitDecl>(DC)) { 1852 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1853 << Name << D.getCXXScopeSpec().getRange(); 1854 } else { 1855 DeclContext *Cur = CurContext; 1856 while (isa<LinkageSpecDecl>(Cur)) 1857 Cur = Cur->getParent(); 1858 if (!Cur->Encloses(DC)) { 1859 // The qualifying scope doesn't enclose the original declaration. 1860 // Emit diagnostic based on current scope. 1861 SourceLocation L = D.getIdentifierLoc(); 1862 SourceRange R = D.getCXXScopeSpec().getRange(); 1863 if (isa<FunctionDecl>(Cur)) 1864 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1865 else 1866 Diag(L, diag::err_invalid_declarator_scope) 1867 << Name << cast<NamedDecl>(DC) << R; 1868 D.setInvalidType(); 1869 } 1870 } 1871 } 1872 1873 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1874 // Maybe we will complain about the shadowed template parameter. 1875 if (!D.isInvalidType()) 1876 if (DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl)) 1877 D.setInvalidType(); 1878 1879 // Just pretend that we didn't see the previous declaration. 1880 PrevDecl = 0; 1881 } 1882 1883 // In C++, the previous declaration we find might be a tag type 1884 // (class or enum). In this case, the new declaration will hide the 1885 // tag type. Note that this does does not apply if we're declaring a 1886 // typedef (C++ [dcl.typedef]p4). 1887 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1888 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1889 PrevDecl = 0; 1890 1891 bool Redeclaration = false; 1892 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1893 if (TemplateParamLists.size()) { 1894 Diag(D.getIdentifierLoc(), diag::err_template_typedef); 1895 return DeclPtrTy(); 1896 } 1897 1898 New = ActOnTypedefDeclarator(S, D, DC, R, DInfo, PrevDecl, Redeclaration); 1899 } else if (R->isFunctionType()) { 1900 New = ActOnFunctionDeclarator(S, D, DC, R, DInfo, PrevDecl, 1901 move(TemplateParamLists), 1902 IsFunctionDefinition, Redeclaration); 1903 } else { 1904 New = ActOnVariableDeclarator(S, D, DC, R, DInfo, PrevDecl, 1905 move(TemplateParamLists), 1906 Redeclaration); 1907 } 1908 1909 if (New == 0) 1910 return DeclPtrTy(); 1911 1912 // If this has an identifier and is not an invalid redeclaration or 1913 // function template specialization, add it to the scope stack. 1914 if (Name && !(Redeclaration && New->isInvalidDecl()) && 1915 !(isa<FunctionDecl>(New) && 1916 cast<FunctionDecl>(New)->isFunctionTemplateSpecialization())) 1917 PushOnScopeChains(New, S); 1918 1919 return DeclPtrTy::make(New); 1920} 1921 1922/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1923/// types into constant array types in certain situations which would otherwise 1924/// be errors (for GCC compatibility). 1925static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1926 ASTContext &Context, 1927 bool &SizeIsNegative) { 1928 // This method tries to turn a variable array into a constant 1929 // array even when the size isn't an ICE. This is necessary 1930 // for compatibility with code that depends on gcc's buggy 1931 // constant expression folding, like struct {char x[(int)(char*)2];} 1932 SizeIsNegative = false; 1933 1934 QualifierCollector Qs; 1935 const Type *Ty = Qs.strip(T); 1936 1937 if (const PointerType* PTy = dyn_cast<PointerType>(Ty)) { 1938 QualType Pointee = PTy->getPointeeType(); 1939 QualType FixedType = 1940 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1941 if (FixedType.isNull()) return FixedType; 1942 FixedType = Context.getPointerType(FixedType); 1943 return Qs.apply(FixedType); 1944 } 1945 1946 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1947 if (!VLATy) 1948 return QualType(); 1949 // FIXME: We should probably handle this case 1950 if (VLATy->getElementType()->isVariablyModifiedType()) 1951 return QualType(); 1952 1953 Expr::EvalResult EvalResult; 1954 if (!VLATy->getSizeExpr() || 1955 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1956 !EvalResult.Val.isInt()) 1957 return QualType(); 1958 1959 llvm::APSInt &Res = EvalResult.Val.getInt(); 1960 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) { 1961 // TODO: preserve the size expression in declarator info 1962 return Context.getConstantArrayType(VLATy->getElementType(), 1963 Res, ArrayType::Normal, 0); 1964 } 1965 1966 SizeIsNegative = true; 1967 return QualType(); 1968} 1969 1970/// \brief Register the given locally-scoped external C declaration so 1971/// that it can be found later for redeclarations 1972void 1973Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1974 Scope *S) { 1975 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1976 "Decl is not a locally-scoped decl!"); 1977 // Note that we have a locally-scoped external with this name. 1978 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1979 1980 if (!PrevDecl) 1981 return; 1982 1983 // If there was a previous declaration of this variable, it may be 1984 // in our identifier chain. Update the identifier chain with the new 1985 // declaration. 1986 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1987 // The previous declaration was found on the identifer resolver 1988 // chain, so remove it from its scope. 1989 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1990 S = S->getParent(); 1991 1992 if (S) 1993 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1994 } 1995} 1996 1997/// \brief Diagnose function specifiers on a declaration of an identifier that 1998/// does not identify a function. 1999void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 2000 // FIXME: We should probably indicate the identifier in question to avoid 2001 // confusion for constructs like "inline int a(), b;" 2002 if (D.getDeclSpec().isInlineSpecified()) 2003 Diag(D.getDeclSpec().getInlineSpecLoc(), 2004 diag::err_inline_non_function); 2005 2006 if (D.getDeclSpec().isVirtualSpecified()) 2007 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2008 diag::err_virtual_non_function); 2009 2010 if (D.getDeclSpec().isExplicitSpecified()) 2011 Diag(D.getDeclSpec().getExplicitSpecLoc(), 2012 diag::err_explicit_non_function); 2013} 2014 2015NamedDecl* 2016Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2017 QualType R, DeclaratorInfo *DInfo, 2018 NamedDecl* PrevDecl, bool &Redeclaration) { 2019 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 2020 if (D.getCXXScopeSpec().isSet()) { 2021 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 2022 << D.getCXXScopeSpec().getRange(); 2023 D.setInvalidType(); 2024 // Pretend we didn't see the scope specifier. 2025 DC = 0; 2026 } 2027 2028 if (getLangOptions().CPlusPlus) { 2029 // Check that there are no default arguments (C++ only). 2030 CheckExtraCXXDefaultArguments(D); 2031 } 2032 2033 DiagnoseFunctionSpecifiers(D); 2034 2035 if (D.getDeclSpec().isThreadSpecified()) 2036 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2037 2038 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R, DInfo); 2039 if (!NewTD) return 0; 2040 2041 // Handle attributes prior to checking for duplicates in MergeVarDecl 2042 ProcessDeclAttributes(S, NewTD, D); 2043 // Merge the decl with the existing one if appropriate. If the decl is 2044 // in an outer scope, it isn't the same thing. 2045 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 2046 Redeclaration = true; 2047 MergeTypeDefDecl(NewTD, PrevDecl); 2048 } 2049 2050 // C99 6.7.7p2: If a typedef name specifies a variably modified type 2051 // then it shall have block scope. 2052 QualType T = NewTD->getUnderlyingType(); 2053 if (T->isVariablyModifiedType()) { 2054 CurFunctionNeedsScopeChecking = true; 2055 2056 if (S->getFnParent() == 0) { 2057 bool SizeIsNegative; 2058 QualType FixedTy = 2059 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2060 if (!FixedTy.isNull()) { 2061 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 2062 NewTD->setTypeDeclaratorInfo(Context.getTrivialDeclaratorInfo(FixedTy)); 2063 } else { 2064 if (SizeIsNegative) 2065 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 2066 else if (T->isVariableArrayType()) 2067 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 2068 else 2069 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 2070 NewTD->setInvalidDecl(); 2071 } 2072 } 2073 } 2074 2075 // If this is the C FILE type, notify the AST context. 2076 if (IdentifierInfo *II = NewTD->getIdentifier()) 2077 if (!NewTD->isInvalidDecl() && 2078 NewTD->getDeclContext()->getLookupContext()->isTranslationUnit()) { 2079 if (II->isStr("FILE")) 2080 Context.setFILEDecl(NewTD); 2081 else if (II->isStr("jmp_buf")) 2082 Context.setjmp_bufDecl(NewTD); 2083 else if (II->isStr("sigjmp_buf")) 2084 Context.setsigjmp_bufDecl(NewTD); 2085 } 2086 2087 return NewTD; 2088} 2089 2090/// \brief Determines whether the given declaration is an out-of-scope 2091/// previous declaration. 2092/// 2093/// This routine should be invoked when name lookup has found a 2094/// previous declaration (PrevDecl) that is not in the scope where a 2095/// new declaration by the same name is being introduced. If the new 2096/// declaration occurs in a local scope, previous declarations with 2097/// linkage may still be considered previous declarations (C99 2098/// 6.2.2p4-5, C++ [basic.link]p6). 2099/// 2100/// \param PrevDecl the previous declaration found by name 2101/// lookup 2102/// 2103/// \param DC the context in which the new declaration is being 2104/// declared. 2105/// 2106/// \returns true if PrevDecl is an out-of-scope previous declaration 2107/// for a new delcaration with the same name. 2108static bool 2109isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 2110 ASTContext &Context) { 2111 if (!PrevDecl) 2112 return 0; 2113 2114 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 2115 // case we need to check each of the overloaded functions. 2116 if (!PrevDecl->hasLinkage()) 2117 return false; 2118 2119 if (Context.getLangOptions().CPlusPlus) { 2120 // C++ [basic.link]p6: 2121 // If there is a visible declaration of an entity with linkage 2122 // having the same name and type, ignoring entities declared 2123 // outside the innermost enclosing namespace scope, the block 2124 // scope declaration declares that same entity and receives the 2125 // linkage of the previous declaration. 2126 DeclContext *OuterContext = DC->getLookupContext(); 2127 if (!OuterContext->isFunctionOrMethod()) 2128 // This rule only applies to block-scope declarations. 2129 return false; 2130 else { 2131 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 2132 if (PrevOuterContext->isRecord()) 2133 // We found a member function: ignore it. 2134 return false; 2135 else { 2136 // Find the innermost enclosing namespace for the new and 2137 // previous declarations. 2138 while (!OuterContext->isFileContext()) 2139 OuterContext = OuterContext->getParent(); 2140 while (!PrevOuterContext->isFileContext()) 2141 PrevOuterContext = PrevOuterContext->getParent(); 2142 2143 // The previous declaration is in a different namespace, so it 2144 // isn't the same function. 2145 if (OuterContext->getPrimaryContext() != 2146 PrevOuterContext->getPrimaryContext()) 2147 return false; 2148 } 2149 } 2150 } 2151 2152 return true; 2153} 2154 2155NamedDecl* 2156Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2157 QualType R, DeclaratorInfo *DInfo, 2158 NamedDecl* PrevDecl, 2159 MultiTemplateParamsArg TemplateParamLists, 2160 bool &Redeclaration) { 2161 DeclarationName Name = GetNameForDeclarator(D); 2162 2163 // Check that there are no default arguments (C++ only). 2164 if (getLangOptions().CPlusPlus) 2165 CheckExtraCXXDefaultArguments(D); 2166 2167 VarDecl *NewVD; 2168 VarDecl::StorageClass SC; 2169 switch (D.getDeclSpec().getStorageClassSpec()) { 2170 default: assert(0 && "Unknown storage class!"); 2171 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 2172 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 2173 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 2174 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 2175 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 2176 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 2177 case DeclSpec::SCS_mutable: 2178 // mutable can only appear on non-static class members, so it's always 2179 // an error here 2180 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 2181 D.setInvalidType(); 2182 SC = VarDecl::None; 2183 break; 2184 } 2185 2186 IdentifierInfo *II = Name.getAsIdentifierInfo(); 2187 if (!II) { 2188 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 2189 << Name.getAsString(); 2190 return 0; 2191 } 2192 2193 DiagnoseFunctionSpecifiers(D); 2194 2195 if (!DC->isRecord() && S->getFnParent() == 0) { 2196 // C99 6.9p2: The storage-class specifiers auto and register shall not 2197 // appear in the declaration specifiers in an external declaration. 2198 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 2199 2200 // If this is a register variable with an asm label specified, then this 2201 // is a GNU extension. 2202 if (SC == VarDecl::Register && D.getAsmLabel()) 2203 Diag(D.getIdentifierLoc(), diag::err_unsupported_global_register); 2204 else 2205 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 2206 D.setInvalidType(); 2207 } 2208 } 2209 if (DC->isRecord() && !CurContext->isRecord()) { 2210 // This is an out-of-line definition of a static data member. 2211 if (SC == VarDecl::Static) { 2212 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2213 diag::err_static_out_of_line) 2214 << CodeModificationHint::CreateRemoval( 2215 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2216 } else if (SC == VarDecl::None) 2217 SC = VarDecl::Static; 2218 } 2219 if (SC == VarDecl::Static) { 2220 if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC)) { 2221 if (RD->isLocalClass()) 2222 Diag(D.getIdentifierLoc(), 2223 diag::err_static_data_member_not_allowed_in_local_class) 2224 << Name << RD->getDeclName(); 2225 } 2226 } 2227 2228 // Match up the template parameter lists with the scope specifier, then 2229 // determine whether we have a template or a template specialization. 2230 bool isExplicitSpecialization = false; 2231 if (TemplateParameterList *TemplateParams 2232 = MatchTemplateParametersToScopeSpecifier( 2233 D.getDeclSpec().getSourceRange().getBegin(), 2234 D.getCXXScopeSpec(), 2235 (TemplateParameterList**)TemplateParamLists.get(), 2236 TemplateParamLists.size(), 2237 isExplicitSpecialization)) { 2238 if (TemplateParams->size() > 0) { 2239 // There is no such thing as a variable template. 2240 Diag(D.getIdentifierLoc(), diag::err_template_variable) 2241 << II 2242 << SourceRange(TemplateParams->getTemplateLoc(), 2243 TemplateParams->getRAngleLoc()); 2244 return 0; 2245 } else { 2246 // There is an extraneous 'template<>' for this variable. Complain 2247 // about it, but allow the declaration of the variable. 2248 Diag(TemplateParams->getTemplateLoc(), 2249 diag::err_template_variable_noparams) 2250 << II 2251 << SourceRange(TemplateParams->getTemplateLoc(), 2252 TemplateParams->getRAngleLoc()); 2253 2254 isExplicitSpecialization = true; 2255 } 2256 } 2257 2258 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 2259 II, R, DInfo, SC); 2260 2261 if (D.isInvalidType()) 2262 NewVD->setInvalidDecl(); 2263 2264 if (D.getDeclSpec().isThreadSpecified()) { 2265 if (NewVD->hasLocalStorage()) 2266 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_non_global); 2267 else if (!Context.Target.isTLSSupported()) 2268 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_thread_unsupported); 2269 else 2270 NewVD->setThreadSpecified(true); 2271 } 2272 2273 // Set the lexical context. If the declarator has a C++ scope specifier, the 2274 // lexical context will be different from the semantic context. 2275 NewVD->setLexicalDeclContext(CurContext); 2276 2277 // Handle attributes prior to checking for duplicates in MergeVarDecl 2278 ProcessDeclAttributes(S, NewVD, D); 2279 2280 // Handle GNU asm-label extension (encoded as an attribute). 2281 if (Expr *E = (Expr*) D.getAsmLabel()) { 2282 // The parser guarantees this is a string. 2283 StringLiteral *SE = cast<StringLiteral>(E); 2284 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2285 SE->getByteLength()))); 2286 } 2287 2288 // If name lookup finds a previous declaration that is not in the 2289 // same scope as the new declaration, this may still be an 2290 // acceptable redeclaration. 2291 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2292 !(NewVD->hasLinkage() && 2293 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2294 PrevDecl = 0; 2295 2296 // Merge the decl with the existing one if appropriate. 2297 if (PrevDecl) { 2298 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 2299 // The user tried to define a non-static data member 2300 // out-of-line (C++ [dcl.meaning]p1). 2301 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 2302 << D.getCXXScopeSpec().getRange(); 2303 PrevDecl = 0; 2304 NewVD->setInvalidDecl(); 2305 } 2306 } else if (D.getCXXScopeSpec().isSet()) { 2307 // No previous declaration in the qualifying scope. 2308 Diag(D.getIdentifierLoc(), diag::err_no_member) 2309 << Name << computeDeclContext(D.getCXXScopeSpec(), true) 2310 << D.getCXXScopeSpec().getRange(); 2311 NewVD->setInvalidDecl(); 2312 } 2313 2314 CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration); 2315 2316 // This is an explicit specialization of a static data member. Check it. 2317 if (isExplicitSpecialization && !NewVD->isInvalidDecl() && 2318 CheckMemberSpecialization(NewVD, PrevDecl)) 2319 NewVD->setInvalidDecl(); 2320 2321 // attributes declared post-definition are currently ignored 2322 if (PrevDecl) { 2323 const VarDecl *Def = 0, *PrevVD = dyn_cast<VarDecl>(PrevDecl); 2324 if (PrevVD->getDefinition(Def) && D.hasAttributes()) { 2325 Diag(NewVD->getLocation(), diag::warn_attribute_precede_definition); 2326 Diag(Def->getLocation(), diag::note_previous_definition); 2327 } 2328 } 2329 2330 // If this is a locally-scoped extern C variable, update the map of 2331 // such variables. 2332 if (CurContext->isFunctionOrMethod() && NewVD->isExternC() && 2333 !NewVD->isInvalidDecl()) 2334 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 2335 2336 return NewVD; 2337} 2338 2339/// \brief Perform semantic checking on a newly-created variable 2340/// declaration. 2341/// 2342/// This routine performs all of the type-checking required for a 2343/// variable declaration once it has been built. It is used both to 2344/// check variables after they have been parsed and their declarators 2345/// have been translated into a declaration, and to check variables 2346/// that have been instantiated from a template. 2347/// 2348/// Sets NewVD->isInvalidDecl() if an error was encountered. 2349void Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 2350 bool &Redeclaration) { 2351 // If the decl is already known invalid, don't check it. 2352 if (NewVD->isInvalidDecl()) 2353 return; 2354 2355 QualType T = NewVD->getType(); 2356 2357 if (T->isObjCInterfaceType()) { 2358 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 2359 return NewVD->setInvalidDecl(); 2360 } 2361 2362 // The variable can not have an abstract class type. 2363 if (RequireNonAbstractType(NewVD->getLocation(), T, 2364 diag::err_abstract_type_in_decl, 2365 AbstractVariableType)) 2366 return NewVD->setInvalidDecl(); 2367 2368 // Emit an error if an address space was applied to decl with local storage. 2369 // This includes arrays of objects with address space qualifiers, but not 2370 // automatic variables that point to other address spaces. 2371 // ISO/IEC TR 18037 S5.1.2 2372 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 2373 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 2374 return NewVD->setInvalidDecl(); 2375 } 2376 2377 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 2378 && !NewVD->hasAttr<BlocksAttr>()) 2379 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 2380 2381 bool isVM = T->isVariablyModifiedType(); 2382 if (isVM || NewVD->hasAttr<CleanupAttr>() || 2383 NewVD->hasAttr<BlocksAttr>()) 2384 CurFunctionNeedsScopeChecking = true; 2385 2386 if ((isVM && NewVD->hasLinkage()) || 2387 (T->isVariableArrayType() && NewVD->hasGlobalStorage())) { 2388 bool SizeIsNegative; 2389 QualType FixedTy = 2390 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 2391 2392 if (FixedTy.isNull() && T->isVariableArrayType()) { 2393 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 2394 // FIXME: This won't give the correct result for 2395 // int a[10][n]; 2396 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 2397 2398 if (NewVD->isFileVarDecl()) 2399 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 2400 << SizeRange; 2401 else if (NewVD->getStorageClass() == VarDecl::Static) 2402 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 2403 << SizeRange; 2404 else 2405 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 2406 << SizeRange; 2407 return NewVD->setInvalidDecl(); 2408 } 2409 2410 if (FixedTy.isNull()) { 2411 if (NewVD->isFileVarDecl()) 2412 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 2413 else 2414 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 2415 return NewVD->setInvalidDecl(); 2416 } 2417 2418 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 2419 NewVD->setType(FixedTy); 2420 } 2421 2422 if (!PrevDecl && NewVD->isExternC()) { 2423 // Since we did not find anything by this name and we're declaring 2424 // an extern "C" variable, look for a non-visible extern "C" 2425 // declaration with the same name. 2426 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2427 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 2428 if (Pos != LocallyScopedExternalDecls.end()) 2429 PrevDecl = Pos->second; 2430 } 2431 2432 if (T->isVoidType() && !NewVD->hasExternalStorage()) { 2433 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 2434 << T; 2435 return NewVD->setInvalidDecl(); 2436 } 2437 2438 if (!NewVD->hasLocalStorage() && NewVD->hasAttr<BlocksAttr>()) { 2439 Diag(NewVD->getLocation(), diag::err_block_on_nonlocal); 2440 return NewVD->setInvalidDecl(); 2441 } 2442 2443 if (isVM && NewVD->hasAttr<BlocksAttr>()) { 2444 Diag(NewVD->getLocation(), diag::err_block_on_vm); 2445 return NewVD->setInvalidDecl(); 2446 } 2447 2448 if (PrevDecl) { 2449 Redeclaration = true; 2450 MergeVarDecl(NewVD, PrevDecl); 2451 } 2452} 2453 2454static bool isUsingDecl(Decl *D) { 2455 return isa<UsingDecl>(D) || 2456 isa<UnresolvedUsingTypenameDecl>(D) || 2457 isa<UnresolvedUsingValueDecl>(D); 2458} 2459 2460/// \brief Data used with FindOverriddenMethod 2461struct FindOverriddenMethodData { 2462 Sema *S; 2463 CXXMethodDecl *Method; 2464}; 2465 2466/// \brief Member lookup function that determines whether a given C++ 2467/// method overrides a method in a base class, to be used with 2468/// CXXRecordDecl::lookupInBases(). 2469static bool FindOverriddenMethod(const CXXBaseSpecifier *Specifier, 2470 CXXBasePath &Path, 2471 void *UserData) { 2472 RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl(); 2473 2474 FindOverriddenMethodData *Data 2475 = reinterpret_cast<FindOverriddenMethodData*>(UserData); 2476 for (Path.Decls = BaseRecord->lookup(Data->Method->getDeclName()); 2477 Path.Decls.first != Path.Decls.second; 2478 ++Path.Decls.first) { 2479 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*Path.Decls.first)) { 2480 OverloadedFunctionDecl::function_iterator MatchedDecl; 2481 if (MD->isVirtual() && !Data->S->IsOverload(Data->Method, MD, MatchedDecl)) 2482 return true; 2483 } 2484 } 2485 2486 return false; 2487} 2488 2489NamedDecl* 2490Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 2491 QualType R, DeclaratorInfo *DInfo, 2492 NamedDecl* PrevDecl, 2493 MultiTemplateParamsArg TemplateParamLists, 2494 bool IsFunctionDefinition, bool &Redeclaration) { 2495 assert(R.getTypePtr()->isFunctionType()); 2496 2497 DeclarationName Name = GetNameForDeclarator(D); 2498 FunctionDecl::StorageClass SC = FunctionDecl::None; 2499 switch (D.getDeclSpec().getStorageClassSpec()) { 2500 default: assert(0 && "Unknown storage class!"); 2501 case DeclSpec::SCS_auto: 2502 case DeclSpec::SCS_register: 2503 case DeclSpec::SCS_mutable: 2504 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2505 diag::err_typecheck_sclass_func); 2506 D.setInvalidType(); 2507 break; 2508 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 2509 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 2510 case DeclSpec::SCS_static: { 2511 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 2512 // C99 6.7.1p5: 2513 // The declaration of an identifier for a function that has 2514 // block scope shall have no explicit storage-class specifier 2515 // other than extern 2516 // See also (C++ [dcl.stc]p4). 2517 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2518 diag::err_static_block_func); 2519 SC = FunctionDecl::None; 2520 } else 2521 SC = FunctionDecl::Static; 2522 break; 2523 } 2524 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 2525 } 2526 2527 if (D.getDeclSpec().isThreadSpecified()) 2528 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 2529 2530 bool isFriend = D.getDeclSpec().isFriendSpecified(); 2531 bool isInline = D.getDeclSpec().isInlineSpecified(); 2532 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 2533 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 2534 2535 // Check that the return type is not an abstract class type. 2536 // For record types, this is done by the AbstractClassUsageDiagnoser once 2537 // the class has been completely parsed. 2538 if (!DC->isRecord() && 2539 RequireNonAbstractType(D.getIdentifierLoc(), 2540 R->getAs<FunctionType>()->getResultType(), 2541 diag::err_abstract_type_in_decl, 2542 AbstractReturnType)) 2543 D.setInvalidType(); 2544 2545 // Do not allow returning a objc interface by-value. 2546 if (R->getAs<FunctionType>()->getResultType()->isObjCInterfaceType()) { 2547 Diag(D.getIdentifierLoc(), 2548 diag::err_object_cannot_be_passed_returned_by_value) << 0 2549 << R->getAs<FunctionType>()->getResultType(); 2550 D.setInvalidType(); 2551 } 2552 2553 bool isVirtualOkay = false; 2554 FunctionDecl *NewFD; 2555 2556 if (isFriend) { 2557 // DC is the namespace in which the function is being declared. 2558 assert((DC->isFileContext() || PrevDecl) && "previously-undeclared " 2559 "friend function being created in a non-namespace context"); 2560 2561 // C++ [class.friend]p5 2562 // A function can be defined in a friend declaration of a 2563 // class . . . . Such a function is implicitly inline. 2564 isInline |= IsFunctionDefinition; 2565 } 2566 2567 if (Name.getNameKind() == DeclarationName::CXXConstructorName) { 2568 // This is a C++ constructor declaration. 2569 assert(DC->isRecord() && 2570 "Constructors can only be declared in a member context"); 2571 2572 R = CheckConstructorDeclarator(D, R, SC); 2573 2574 // Create the new declaration 2575 NewFD = CXXConstructorDecl::Create(Context, 2576 cast<CXXRecordDecl>(DC), 2577 D.getIdentifierLoc(), Name, R, DInfo, 2578 isExplicit, isInline, 2579 /*isImplicitlyDeclared=*/false); 2580 } else if (Name.getNameKind() == DeclarationName::CXXDestructorName) { 2581 // This is a C++ destructor declaration. 2582 if (DC->isRecord()) { 2583 R = CheckDestructorDeclarator(D, SC); 2584 2585 NewFD = CXXDestructorDecl::Create(Context, 2586 cast<CXXRecordDecl>(DC), 2587 D.getIdentifierLoc(), Name, R, 2588 isInline, 2589 /*isImplicitlyDeclared=*/false); 2590 2591 isVirtualOkay = true; 2592 } else { 2593 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 2594 2595 // Create a FunctionDecl to satisfy the function definition parsing 2596 // code path. 2597 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 2598 Name, R, DInfo, SC, isInline, 2599 /*hasPrototype=*/true); 2600 D.setInvalidType(); 2601 } 2602 } else if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName) { 2603 if (!DC->isRecord()) { 2604 Diag(D.getIdentifierLoc(), 2605 diag::err_conv_function_not_member); 2606 return 0; 2607 } 2608 2609 CheckConversionDeclarator(D, R, SC); 2610 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 2611 D.getIdentifierLoc(), Name, R, DInfo, 2612 isInline, isExplicit); 2613 2614 isVirtualOkay = true; 2615 } else if (DC->isRecord()) { 2616 // If the of the function is the same as the name of the record, then this 2617 // must be an invalid constructor that has a return type. 2618 // (The parser checks for a return type and makes the declarator a 2619 // constructor if it has no return type). 2620 // must have an invalid constructor that has a return type 2621 if (Name.getAsIdentifierInfo() == cast<CXXRecordDecl>(DC)->getIdentifier()){ 2622 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 2623 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 2624 << SourceRange(D.getIdentifierLoc()); 2625 return 0; 2626 } 2627 2628 bool isStatic = SC == FunctionDecl::Static; 2629 2630 // [class.free]p1: 2631 // Any allocation function for a class T is a static member 2632 // (even if not explicitly declared static). 2633 if (Name.getCXXOverloadedOperator() == OO_New || 2634 Name.getCXXOverloadedOperator() == OO_Array_New) 2635 isStatic = true; 2636 2637 // [class.free]p6 Any deallocation function for a class X is a static member 2638 // (even if not explicitly declared static). 2639 if (Name.getCXXOverloadedOperator() == OO_Delete || 2640 Name.getCXXOverloadedOperator() == OO_Array_Delete) 2641 isStatic = true; 2642 2643 // This is a C++ method declaration. 2644 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 2645 D.getIdentifierLoc(), Name, R, DInfo, 2646 isStatic, isInline); 2647 2648 isVirtualOkay = !isStatic; 2649 } else { 2650 // Determine whether the function was written with a 2651 // prototype. This true when: 2652 // - we're in C++ (where every function has a prototype), 2653 // - there is a prototype in the declarator, or 2654 // - the type R of the function is some kind of typedef or other reference 2655 // to a type name (which eventually refers to a function type). 2656 bool HasPrototype = 2657 getLangOptions().CPlusPlus || 2658 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2659 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2660 2661 NewFD = FunctionDecl::Create(Context, DC, 2662 D.getIdentifierLoc(), 2663 Name, R, DInfo, SC, isInline, HasPrototype); 2664 } 2665 2666 if (D.isInvalidType()) 2667 NewFD->setInvalidDecl(); 2668 2669 // Set the lexical context. If the declarator has a C++ 2670 // scope specifier, or is the object of a friend declaration, the 2671 // lexical context will be different from the semantic context. 2672 NewFD->setLexicalDeclContext(CurContext); 2673 2674 // Match up the template parameter lists with the scope specifier, then 2675 // determine whether we have a template or a template specialization. 2676 FunctionTemplateDecl *FunctionTemplate = 0; 2677 bool isExplicitSpecialization = false; 2678 bool isFunctionTemplateSpecialization = false; 2679 if (TemplateParameterList *TemplateParams 2680 = MatchTemplateParametersToScopeSpecifier( 2681 D.getDeclSpec().getSourceRange().getBegin(), 2682 D.getCXXScopeSpec(), 2683 (TemplateParameterList**)TemplateParamLists.get(), 2684 TemplateParamLists.size(), 2685 isExplicitSpecialization)) { 2686 if (TemplateParams->size() > 0) { 2687 // This is a function template 2688 2689 // Check that we can declare a template here. 2690 if (CheckTemplateDeclScope(S, TemplateParams)) 2691 return 0; 2692 2693 FunctionTemplate = FunctionTemplateDecl::Create(Context, DC, 2694 NewFD->getLocation(), 2695 Name, TemplateParams, 2696 NewFD); 2697 FunctionTemplate->setLexicalDeclContext(CurContext); 2698 NewFD->setDescribedFunctionTemplate(FunctionTemplate); 2699 } else { 2700 // This is a function template specialization. 2701 isFunctionTemplateSpecialization = true; 2702 } 2703 2704 // FIXME: Free this memory properly. 2705 TemplateParamLists.release(); 2706 } 2707 2708 // C++ [dcl.fct.spec]p5: 2709 // The virtual specifier shall only be used in declarations of 2710 // nonstatic class member functions that appear within a 2711 // member-specification of a class declaration; see 10.3. 2712 // 2713 if (isVirtual && !NewFD->isInvalidDecl()) { 2714 if (!isVirtualOkay) { 2715 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2716 diag::err_virtual_non_function); 2717 } else if (!CurContext->isRecord()) { 2718 // 'virtual' was specified outside of the class. 2719 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2720 << CodeModificationHint::CreateRemoval( 2721 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2722 } else { 2723 // Okay: Add virtual to the method. 2724 cast<CXXMethodDecl>(NewFD)->setVirtualAsWritten(true); 2725 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2726 CurClass->setAggregate(false); 2727 CurClass->setPOD(false); 2728 CurClass->setEmpty(false); 2729 CurClass->setPolymorphic(true); 2730 CurClass->setHasTrivialConstructor(false); 2731 CurClass->setHasTrivialCopyConstructor(false); 2732 CurClass->setHasTrivialCopyAssignment(false); 2733 } 2734 } 2735 2736 if (isFriend) { 2737 if (FunctionTemplate) { 2738 FunctionTemplate->setObjectOfFriendDecl( 2739 /* PreviouslyDeclared= */ PrevDecl != NULL); 2740 FunctionTemplate->setAccess(AS_public); 2741 } 2742 else 2743 NewFD->setObjectOfFriendDecl(/* PreviouslyDeclared= */ PrevDecl != NULL); 2744 2745 NewFD->setAccess(AS_public); 2746 } 2747 2748 2749 if (CXXMethodDecl *NewMD = dyn_cast<CXXMethodDecl>(NewFD)) { 2750 // Look for virtual methods in base classes that this method might override. 2751 CXXBasePaths Paths; 2752 FindOverriddenMethodData Data; 2753 Data.Method = NewMD; 2754 Data.S = this; 2755 if (cast<CXXRecordDecl>(DC)->lookupInBases(&FindOverriddenMethod, &Data, 2756 Paths)) { 2757 for (CXXBasePaths::decl_iterator I = Paths.found_decls_begin(), 2758 E = Paths.found_decls_end(); I != E; ++I) { 2759 if (CXXMethodDecl *OldMD = dyn_cast<CXXMethodDecl>(*I)) { 2760 if (!CheckOverridingFunctionReturnType(NewMD, OldMD) && 2761 !CheckOverridingFunctionExceptionSpec(NewMD, OldMD)) 2762 NewMD->addOverriddenMethod(OldMD); 2763 } 2764 } 2765 } 2766 } 2767 2768 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2769 !CurContext->isRecord()) { 2770 // C++ [class.static]p1: 2771 // A data or function member of a class may be declared static 2772 // in a class definition, in which case it is a static member of 2773 // the class. 2774 2775 // Complain about the 'static' specifier if it's on an out-of-line 2776 // member function definition. 2777 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2778 diag::err_static_out_of_line) 2779 << CodeModificationHint::CreateRemoval( 2780 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2781 } 2782 2783 // Handle GNU asm-label extension (encoded as an attribute). 2784 if (Expr *E = (Expr*) D.getAsmLabel()) { 2785 // The parser guarantees this is a string. 2786 StringLiteral *SE = cast<StringLiteral>(E); 2787 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2788 SE->getByteLength()))); 2789 } 2790 2791 // Copy the parameter declarations from the declarator D to the function 2792 // declaration NewFD, if they are available. First scavenge them into Params. 2793 llvm::SmallVector<ParmVarDecl*, 16> Params; 2794 if (D.getNumTypeObjects() > 0) { 2795 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2796 2797 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2798 // function that takes no arguments, not a function that takes a 2799 // single void argument. 2800 // We let through "const void" here because Sema::GetTypeForDeclarator 2801 // already checks for that case. 2802 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2803 FTI.ArgInfo[0].Param && 2804 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2805 // Empty arg list, don't push any params. 2806 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2807 2808 // In C++, the empty parameter-type-list must be spelled "void"; a 2809 // typedef of void is not permitted. 2810 if (getLangOptions().CPlusPlus && 2811 Param->getType().getUnqualifiedType() != Context.VoidTy) 2812 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2813 // FIXME: Leaks decl? 2814 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2815 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) { 2816 ParmVarDecl *Param = FTI.ArgInfo[i].Param.getAs<ParmVarDecl>(); 2817 assert(Param->getDeclContext() != NewFD && "Was set before ?"); 2818 Param->setDeclContext(NewFD); 2819 Params.push_back(Param); 2820 } 2821 } 2822 2823 } else if (const FunctionProtoType *FT = R->getAs<FunctionProtoType>()) { 2824 // When we're declaring a function with a typedef, typeof, etc as in the 2825 // following example, we'll need to synthesize (unnamed) 2826 // parameters for use in the declaration. 2827 // 2828 // @code 2829 // typedef void fn(int); 2830 // fn f; 2831 // @endcode 2832 2833 // Synthesize a parameter for each argument type. 2834 for (FunctionProtoType::arg_type_iterator AI = FT->arg_type_begin(), 2835 AE = FT->arg_type_end(); AI != AE; ++AI) { 2836 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2837 SourceLocation(), 0, 2838 *AI, /*DInfo=*/0, 2839 VarDecl::None, 0); 2840 Param->setImplicit(); 2841 Params.push_back(Param); 2842 } 2843 } else { 2844 assert(R->isFunctionNoProtoType() && NewFD->getNumParams() == 0 && 2845 "Should not need args for typedef of non-prototype fn"); 2846 } 2847 // Finally, we know we have the right number of parameters, install them. 2848 NewFD->setParams(Context, Params.data(), Params.size()); 2849 2850 // If name lookup finds a previous declaration that is not in the 2851 // same scope as the new declaration, this may still be an 2852 // acceptable redeclaration. 2853 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2854 !(NewFD->hasLinkage() && 2855 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2856 PrevDecl = 0; 2857 2858 // If the declarator is a template-id, translate the parser's template 2859 // argument list into our AST format. 2860 bool HasExplicitTemplateArgs = false; 2861 llvm::SmallVector<TemplateArgumentLoc, 16> TemplateArgs; 2862 SourceLocation LAngleLoc, RAngleLoc; 2863 if (D.getName().getKind() == UnqualifiedId::IK_TemplateId) { 2864 TemplateIdAnnotation *TemplateId = D.getName().TemplateId; 2865 ASTTemplateArgsPtr TemplateArgsPtr(*this, 2866 TemplateId->getTemplateArgs(), 2867 TemplateId->NumArgs); 2868 translateTemplateArguments(TemplateArgsPtr, 2869 TemplateArgs); 2870 TemplateArgsPtr.release(); 2871 2872 HasExplicitTemplateArgs = true; 2873 LAngleLoc = TemplateId->LAngleLoc; 2874 RAngleLoc = TemplateId->RAngleLoc; 2875 2876 if (FunctionTemplate) { 2877 // FIXME: Diagnose function template with explicit template 2878 // arguments. 2879 HasExplicitTemplateArgs = false; 2880 } else if (!isFunctionTemplateSpecialization && 2881 !D.getDeclSpec().isFriendSpecified()) { 2882 // We have encountered something that the user meant to be a 2883 // specialization (because it has explicitly-specified template 2884 // arguments) but that was not introduced with a "template<>" (or had 2885 // too few of them). 2886 Diag(D.getIdentifierLoc(), diag::err_template_spec_needs_header) 2887 << SourceRange(TemplateId->LAngleLoc, TemplateId->RAngleLoc) 2888 << CodeModificationHint::CreateInsertion( 2889 D.getDeclSpec().getSourceRange().getBegin(), 2890 "template<> "); 2891 isFunctionTemplateSpecialization = true; 2892 } 2893 } 2894 2895 if (isFunctionTemplateSpecialization) { 2896 if (CheckFunctionTemplateSpecialization(NewFD, HasExplicitTemplateArgs, 2897 LAngleLoc, TemplateArgs.data(), 2898 TemplateArgs.size(), RAngleLoc, 2899 PrevDecl)) 2900 NewFD->setInvalidDecl(); 2901 } else if (isExplicitSpecialization && isa<CXXMethodDecl>(NewFD) && 2902 CheckMemberSpecialization(NewFD, PrevDecl)) 2903 NewFD->setInvalidDecl(); 2904 2905 // Perform semantic checking on the function declaration. 2906 bool OverloadableAttrRequired = false; // FIXME: HACK! 2907 CheckFunctionDeclaration(NewFD, PrevDecl, isExplicitSpecialization, 2908 Redeclaration, /*FIXME:*/OverloadableAttrRequired); 2909 2910 if (D.getCXXScopeSpec().isSet() && !NewFD->isInvalidDecl()) { 2911 // An out-of-line member function declaration must also be a 2912 // definition (C++ [dcl.meaning]p1). 2913 // Note that this is not the case for explicit specializations of 2914 // function templates or member functions of class templates, per 2915 // C++ [temp.expl.spec]p2. 2916 if (!IsFunctionDefinition && !isFriend && 2917 !isFunctionTemplateSpecialization && !isExplicitSpecialization) { 2918 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2919 << D.getCXXScopeSpec().getRange(); 2920 NewFD->setInvalidDecl(); 2921 } else if (!Redeclaration && (!PrevDecl || !isUsingDecl(PrevDecl))) { 2922 // The user tried to provide an out-of-line definition for a 2923 // function that is a member of a class or namespace, but there 2924 // was no such member function declared (C++ [class.mfct]p2, 2925 // C++ [namespace.memdef]p2). For example: 2926 // 2927 // class X { 2928 // void f() const; 2929 // }; 2930 // 2931 // void X::f() { } // ill-formed 2932 // 2933 // Complain about this problem, and attempt to suggest close 2934 // matches (e.g., those that differ only in cv-qualifiers and 2935 // whether the parameter types are references). 2936 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2937 << Name << DC << D.getCXXScopeSpec().getRange(); 2938 NewFD->setInvalidDecl(); 2939 2940 LookupResult Prev(*this, Name, D.getIdentifierLoc(), LookupOrdinaryName, 2941 ForRedeclaration); 2942 LookupQualifiedName(Prev, DC); 2943 assert(!Prev.isAmbiguous() && 2944 "Cannot have an ambiguity in previous-declaration lookup"); 2945 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2946 Func != FuncEnd; ++Func) { 2947 if (isa<FunctionDecl>(*Func) && 2948 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2949 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2950 } 2951 2952 PrevDecl = 0; 2953 } 2954 } 2955 2956 // Handle attributes. We need to have merged decls when handling attributes 2957 // (for example to check for conflicts, etc). 2958 // FIXME: This needs to happen before we merge declarations. Then, 2959 // let attribute merging cope with attribute conflicts. 2960 ProcessDeclAttributes(S, NewFD, D); 2961 2962 // attributes declared post-definition are currently ignored 2963 if (Redeclaration && PrevDecl) { 2964 const FunctionDecl *Def, *PrevFD = dyn_cast<FunctionDecl>(PrevDecl); 2965 if (PrevFD && PrevFD->getBody(Def) && D.hasAttributes()) { 2966 Diag(NewFD->getLocation(), diag::warn_attribute_precede_definition); 2967 Diag(Def->getLocation(), diag::note_previous_definition); 2968 } 2969 } 2970 2971 AddKnownFunctionAttributes(NewFD); 2972 2973 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2974 // If a function name is overloadable in C, then every function 2975 // with that name must be marked "overloadable". 2976 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2977 << Redeclaration << NewFD; 2978 if (PrevDecl) 2979 Diag(PrevDecl->getLocation(), 2980 diag::note_attribute_overloadable_prev_overload); 2981 NewFD->addAttr(::new (Context) OverloadableAttr()); 2982 } 2983 2984 // If this is a locally-scoped extern C function, update the 2985 // map of such names. 2986 if (CurContext->isFunctionOrMethod() && NewFD->isExternC() 2987 && !NewFD->isInvalidDecl()) 2988 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2989 2990 // Set this FunctionDecl's range up to the right paren. 2991 NewFD->setLocEnd(D.getSourceRange().getEnd()); 2992 2993 if (FunctionTemplate && NewFD->isInvalidDecl()) 2994 FunctionTemplate->setInvalidDecl(); 2995 2996 if (FunctionTemplate) 2997 return FunctionTemplate; 2998 2999 return NewFD; 3000} 3001 3002/// \brief Perform semantic checking of a new function declaration. 3003/// 3004/// Performs semantic analysis of the new function declaration 3005/// NewFD. This routine performs all semantic checking that does not 3006/// require the actual declarator involved in the declaration, and is 3007/// used both for the declaration of functions as they are parsed 3008/// (called via ActOnDeclarator) and for the declaration of functions 3009/// that have been instantiated via C++ template instantiation (called 3010/// via InstantiateDecl). 3011/// 3012/// \param IsExplicitSpecialiation whether this new function declaration is 3013/// an explicit specialization of the previous declaration. 3014/// 3015/// This sets NewFD->isInvalidDecl() to true if there was an error. 3016void Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 3017 bool IsExplicitSpecialization, 3018 bool &Redeclaration, 3019 bool &OverloadableAttrRequired) { 3020 // If NewFD is already known erroneous, don't do any of this checking. 3021 if (NewFD->isInvalidDecl()) 3022 return; 3023 3024 if (NewFD->getResultType()->isVariablyModifiedType()) { 3025 // Functions returning a variably modified type violate C99 6.7.5.2p2 3026 // because all functions have linkage. 3027 Diag(NewFD->getLocation(), diag::err_vm_func_decl); 3028 return NewFD->setInvalidDecl(); 3029 } 3030 3031 if (NewFD->isMain()) 3032 CheckMain(NewFD); 3033 3034 // Check for a previous declaration of this name. 3035 if (!PrevDecl && NewFD->isExternC()) { 3036 // Since we did not find anything by this name and we're declaring 3037 // an extern "C" function, look for a non-visible extern "C" 3038 // declaration with the same name. 3039 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3040 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 3041 if (Pos != LocallyScopedExternalDecls.end()) 3042 PrevDecl = Pos->second; 3043 } 3044 3045 // Merge or overload the declaration with an existing declaration of 3046 // the same name, if appropriate. 3047 if (PrevDecl) { 3048 // Determine whether NewFD is an overload of PrevDecl or 3049 // a declaration that requires merging. If it's an overload, 3050 // there's no more work to do here; we'll just add the new 3051 // function to the scope. 3052 OverloadedFunctionDecl::function_iterator MatchedDecl; 3053 3054 if (!getLangOptions().CPlusPlus && 3055 AllowOverloadingOfFunction(PrevDecl, Context)) { 3056 OverloadableAttrRequired = true; 3057 3058 // Functions marked "overloadable" must have a prototype (that 3059 // we can't get through declaration merging). 3060 if (!NewFD->getType()->getAs<FunctionProtoType>()) { 3061 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 3062 << NewFD; 3063 Redeclaration = true; 3064 3065 // Turn this into a variadic function with no parameters. 3066 QualType R = Context.getFunctionType( 3067 NewFD->getType()->getAs<FunctionType>()->getResultType(), 3068 0, 0, true, 0); 3069 NewFD->setType(R); 3070 return NewFD->setInvalidDecl(); 3071 } 3072 } 3073 3074 if (PrevDecl && 3075 (!AllowOverloadingOfFunction(PrevDecl, Context) || 3076 !IsOverload(NewFD, PrevDecl, MatchedDecl)) && !isUsingDecl(PrevDecl)) { 3077 Redeclaration = true; 3078 Decl *OldDecl = PrevDecl; 3079 3080 // If PrevDecl was an overloaded function, extract the 3081 // FunctionDecl that matched. 3082 if (isa<OverloadedFunctionDecl>(PrevDecl)) 3083 OldDecl = *MatchedDecl; 3084 3085 // NewFD and OldDecl represent declarations that need to be 3086 // merged. 3087 if (MergeFunctionDecl(NewFD, OldDecl)) 3088 return NewFD->setInvalidDecl(); 3089 3090 if (FunctionTemplateDecl *OldTemplateDecl 3091 = dyn_cast<FunctionTemplateDecl>(OldDecl)) { 3092 NewFD->setPreviousDeclaration(OldTemplateDecl->getTemplatedDecl()); 3093 FunctionTemplateDecl *NewTemplateDecl 3094 = NewFD->getDescribedFunctionTemplate(); 3095 assert(NewTemplateDecl && "Template/non-template mismatch"); 3096 if (CXXMethodDecl *Method 3097 = dyn_cast<CXXMethodDecl>(NewTemplateDecl->getTemplatedDecl())) { 3098 Method->setAccess(OldTemplateDecl->getAccess()); 3099 NewTemplateDecl->setAccess(OldTemplateDecl->getAccess()); 3100 } 3101 3102 // If this is an explicit specialization of a member that is a function 3103 // template, mark it as a member specialization. 3104 if (IsExplicitSpecialization && 3105 NewTemplateDecl->getInstantiatedFromMemberTemplate()) { 3106 NewTemplateDecl->setMemberSpecialization(); 3107 assert(OldTemplateDecl->isMemberSpecialization()); 3108 } 3109 } else { 3110 if (isa<CXXMethodDecl>(NewFD)) // Set access for out-of-line definitions 3111 NewFD->setAccess(OldDecl->getAccess()); 3112 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 3113 } 3114 } 3115 } 3116 3117 // Semantic checking for this function declaration (in isolation). 3118 if (getLangOptions().CPlusPlus) { 3119 // C++-specific checks. 3120 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) { 3121 CheckConstructor(Constructor); 3122 } else if (CXXDestructorDecl *Destructor = 3123 dyn_cast<CXXDestructorDecl>(NewFD)) { 3124 CXXRecordDecl *Record = Destructor->getParent(); 3125 QualType ClassType = Context.getTypeDeclType(Record); 3126 3127 // FIXME: Shouldn't we be able to perform thisc heck even when the class 3128 // type is dependent? Both gcc and edg can handle that. 3129 if (!ClassType->isDependentType()) { 3130 DeclarationName Name 3131 = Context.DeclarationNames.getCXXDestructorName( 3132 Context.getCanonicalType(ClassType)); 3133 if (NewFD->getDeclName() != Name) { 3134 Diag(NewFD->getLocation(), diag::err_destructor_name); 3135 return NewFD->setInvalidDecl(); 3136 } 3137 3138 CheckDestructor(Destructor); 3139 } 3140 3141 Record->setUserDeclaredDestructor(true); 3142 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 3143 // user-defined destructor. 3144 Record->setPOD(false); 3145 3146 // C++ [class.dtor]p3: A destructor is trivial if it is an implicitly- 3147 // declared destructor. 3148 // FIXME: C++0x: don't do this for "= default" destructors 3149 Record->setHasTrivialDestructor(false); 3150 } else if (CXXConversionDecl *Conversion 3151 = dyn_cast<CXXConversionDecl>(NewFD)) 3152 ActOnConversionDeclarator(Conversion); 3153 3154 // Extra checking for C++ overloaded operators (C++ [over.oper]). 3155 if (NewFD->isOverloadedOperator() && 3156 CheckOverloadedOperatorDeclaration(NewFD)) 3157 return NewFD->setInvalidDecl(); 3158 3159 // In C++, check default arguments now that we have merged decls. Unless 3160 // the lexical context is the class, because in this case this is done 3161 // during delayed parsing anyway. 3162 if (!CurContext->isRecord()) 3163 CheckCXXDefaultArguments(NewFD); 3164 } 3165} 3166 3167void Sema::CheckMain(FunctionDecl* FD) { 3168 // C++ [basic.start.main]p3: A program that declares main to be inline 3169 // or static is ill-formed. 3170 // C99 6.7.4p4: In a hosted environment, the inline function specifier 3171 // shall not appear in a declaration of main. 3172 // static main is not an error under C99, but we should warn about it. 3173 bool isInline = FD->isInlineSpecified(); 3174 bool isStatic = FD->getStorageClass() == FunctionDecl::Static; 3175 if (isInline || isStatic) { 3176 unsigned diagID = diag::warn_unusual_main_decl; 3177 if (isInline || getLangOptions().CPlusPlus) 3178 diagID = diag::err_unusual_main_decl; 3179 3180 int which = isStatic + (isInline << 1) - 1; 3181 Diag(FD->getLocation(), diagID) << which; 3182 } 3183 3184 QualType T = FD->getType(); 3185 assert(T->isFunctionType() && "function decl is not of function type"); 3186 const FunctionType* FT = T->getAs<FunctionType>(); 3187 3188 if (!Context.hasSameUnqualifiedType(FT->getResultType(), Context.IntTy)) { 3189 // TODO: add a replacement fixit to turn the return type into 'int'. 3190 Diag(FD->getTypeSpecStartLoc(), diag::err_main_returns_nonint); 3191 FD->setInvalidDecl(true); 3192 } 3193 3194 // Treat protoless main() as nullary. 3195 if (isa<FunctionNoProtoType>(FT)) return; 3196 3197 const FunctionProtoType* FTP = cast<const FunctionProtoType>(FT); 3198 unsigned nparams = FTP->getNumArgs(); 3199 assert(FD->getNumParams() == nparams); 3200 3201 if (nparams > 3) { 3202 Diag(FD->getLocation(), diag::err_main_surplus_args) << nparams; 3203 FD->setInvalidDecl(true); 3204 nparams = 3; 3205 } 3206 3207 // FIXME: a lot of the following diagnostics would be improved 3208 // if we had some location information about types. 3209 3210 QualType CharPP = 3211 Context.getPointerType(Context.getPointerType(Context.CharTy)); 3212 QualType Expected[] = { Context.IntTy, CharPP, CharPP }; 3213 3214 for (unsigned i = 0; i < nparams; ++i) { 3215 QualType AT = FTP->getArgType(i); 3216 3217 bool mismatch = true; 3218 3219 if (Context.hasSameUnqualifiedType(AT, Expected[i])) 3220 mismatch = false; 3221 else if (Expected[i] == CharPP) { 3222 // As an extension, the following forms are okay: 3223 // char const ** 3224 // char const * const * 3225 // char * const * 3226 3227 QualifierCollector qs; 3228 const PointerType* PT; 3229 if ((PT = qs.strip(AT)->getAs<PointerType>()) && 3230 (PT = qs.strip(PT->getPointeeType())->getAs<PointerType>()) && 3231 (QualType(qs.strip(PT->getPointeeType()), 0) == Context.CharTy)) { 3232 qs.removeConst(); 3233 mismatch = !qs.empty(); 3234 } 3235 } 3236 3237 if (mismatch) { 3238 Diag(FD->getLocation(), diag::err_main_arg_wrong) << i << Expected[i]; 3239 // TODO: suggest replacing given type with expected type 3240 FD->setInvalidDecl(true); 3241 } 3242 } 3243 3244 if (nparams == 1 && !FD->isInvalidDecl()) { 3245 Diag(FD->getLocation(), diag::warn_main_one_arg); 3246 } 3247} 3248 3249bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 3250 // FIXME: Need strict checking. In C89, we need to check for 3251 // any assignment, increment, decrement, function-calls, or 3252 // commas outside of a sizeof. In C99, it's the same list, 3253 // except that the aforementioned are allowed in unevaluated 3254 // expressions. Everything else falls under the 3255 // "may accept other forms of constant expressions" exception. 3256 // (We never end up here for C++, so the constant expression 3257 // rules there don't matter.) 3258 if (Init->isConstantInitializer(Context)) 3259 return false; 3260 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 3261 << Init->getSourceRange(); 3262 return true; 3263} 3264 3265void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 3266 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 3267} 3268 3269/// AddInitializerToDecl - Adds the initializer Init to the 3270/// declaration dcl. If DirectInit is true, this is C++ direct 3271/// initialization rather than copy initialization. 3272void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 3273 Decl *RealDecl = dcl.getAs<Decl>(); 3274 // If there is no declaration, there was an error parsing it. Just ignore 3275 // the initializer. 3276 if (RealDecl == 0) 3277 return; 3278 3279 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 3280 // With declarators parsed the way they are, the parser cannot 3281 // distinguish between a normal initializer and a pure-specifier. 3282 // Thus this grotesque test. 3283 IntegerLiteral *IL; 3284 Expr *Init = static_cast<Expr *>(init.get()); 3285 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 3286 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 3287 if (Method->isVirtualAsWritten()) { 3288 Method->setPure(); 3289 3290 // A class is abstract if at least one function is pure virtual. 3291 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 3292 } else if (!Method->isInvalidDecl()) { 3293 Diag(Method->getLocation(), diag::err_non_virtual_pure) 3294 << Method->getDeclName() << Init->getSourceRange(); 3295 Method->setInvalidDecl(); 3296 } 3297 } else { 3298 Diag(Method->getLocation(), diag::err_member_function_initialization) 3299 << Method->getDeclName() << Init->getSourceRange(); 3300 Method->setInvalidDecl(); 3301 } 3302 return; 3303 } 3304 3305 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 3306 if (!VDecl) { 3307 if (getLangOptions().CPlusPlus && 3308 RealDecl->getLexicalDeclContext()->isRecord() && 3309 isa<NamedDecl>(RealDecl)) 3310 Diag(RealDecl->getLocation(), diag::err_member_initialization) 3311 << cast<NamedDecl>(RealDecl)->getDeclName(); 3312 else 3313 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 3314 RealDecl->setInvalidDecl(); 3315 return; 3316 } 3317 3318 // A definition must end up with a complete type, which means it must be 3319 // complete with the restriction that an array type might be completed by the 3320 // initializer; note that later code assumes this restriction. 3321 QualType BaseDeclType = VDecl->getType(); 3322 if (const ArrayType *Array = Context.getAsIncompleteArrayType(BaseDeclType)) 3323 BaseDeclType = Array->getElementType(); 3324 if (RequireCompleteType(VDecl->getLocation(), BaseDeclType, 3325 diag::err_typecheck_decl_incomplete_type)) { 3326 RealDecl->setInvalidDecl(); 3327 return; 3328 } 3329 3330 const VarDecl *Def = 0; 3331 if (VDecl->getDefinition(Def)) { 3332 Diag(VDecl->getLocation(), diag::err_redefinition) 3333 << VDecl->getDeclName(); 3334 Diag(Def->getLocation(), diag::note_previous_definition); 3335 VDecl->setInvalidDecl(); 3336 return; 3337 } 3338 3339 // Take ownership of the expression, now that we're sure we have somewhere 3340 // to put it. 3341 Expr *Init = init.takeAs<Expr>(); 3342 assert(Init && "missing initializer"); 3343 3344 // Get the decls type and save a reference for later, since 3345 // CheckInitializerTypes may change it. 3346 QualType DclT = VDecl->getType(), SavT = DclT; 3347 if (VDecl->isBlockVarDecl()) { 3348 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 3349 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 3350 VDecl->setInvalidDecl(); 3351 } else if (!VDecl->isInvalidDecl()) { 3352 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3353 VDecl->getDeclName(), DirectInit)) 3354 VDecl->setInvalidDecl(); 3355 3356 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3357 // Don't check invalid declarations to avoid emitting useless diagnostics. 3358 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3359 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 3360 CheckForConstantInitializer(Init, DclT); 3361 } 3362 } 3363 } else if (VDecl->isStaticDataMember() && 3364 VDecl->getLexicalDeclContext()->isRecord()) { 3365 // This is an in-class initialization for a static data member, e.g., 3366 // 3367 // struct S { 3368 // static const int value = 17; 3369 // }; 3370 3371 // Attach the initializer 3372 VDecl->setInit(Context, Init); 3373 3374 // C++ [class.mem]p4: 3375 // A member-declarator can contain a constant-initializer only 3376 // if it declares a static member (9.4) of const integral or 3377 // const enumeration type, see 9.4.2. 3378 QualType T = VDecl->getType(); 3379 if (!T->isDependentType() && 3380 (!Context.getCanonicalType(T).isConstQualified() || 3381 !T->isIntegralType())) { 3382 Diag(VDecl->getLocation(), diag::err_member_initialization) 3383 << VDecl->getDeclName() << Init->getSourceRange(); 3384 VDecl->setInvalidDecl(); 3385 } else { 3386 // C++ [class.static.data]p4: 3387 // If a static data member is of const integral or const 3388 // enumeration type, its declaration in the class definition 3389 // can specify a constant-initializer which shall be an 3390 // integral constant expression (5.19). 3391 if (!Init->isTypeDependent() && 3392 !Init->getType()->isIntegralType()) { 3393 // We have a non-dependent, non-integral or enumeration type. 3394 Diag(Init->getSourceRange().getBegin(), 3395 diag::err_in_class_initializer_non_integral_type) 3396 << Init->getType() << Init->getSourceRange(); 3397 VDecl->setInvalidDecl(); 3398 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 3399 // Check whether the expression is a constant expression. 3400 llvm::APSInt Value; 3401 SourceLocation Loc; 3402 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 3403 Diag(Loc, diag::err_in_class_initializer_non_constant) 3404 << Init->getSourceRange(); 3405 VDecl->setInvalidDecl(); 3406 } else if (!VDecl->getType()->isDependentType()) 3407 ImpCastExprToType(Init, VDecl->getType(), CastExpr::CK_IntegralCast); 3408 } 3409 } 3410 } else if (VDecl->isFileVarDecl()) { 3411 if (VDecl->getStorageClass() == VarDecl::Extern) 3412 Diag(VDecl->getLocation(), diag::warn_extern_init); 3413 if (!VDecl->isInvalidDecl()) 3414 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 3415 VDecl->getDeclName(), DirectInit)) 3416 VDecl->setInvalidDecl(); 3417 3418 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 3419 // Don't check invalid declarations to avoid emitting useless diagnostics. 3420 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 3421 // C99 6.7.8p4. All file scoped initializers need to be constant. 3422 CheckForConstantInitializer(Init, DclT); 3423 } 3424 } 3425 // If the type changed, it means we had an incomplete type that was 3426 // completed by the initializer. For example: 3427 // int ary[] = { 1, 3, 5 }; 3428 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 3429 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 3430 VDecl->setType(DclT); 3431 Init->setType(DclT); 3432 } 3433 3434 Init = MaybeCreateCXXExprWithTemporaries(Init, 3435 /*ShouldDestroyTemporaries=*/true); 3436 // Attach the initializer to the decl. 3437 VDecl->setInit(Context, Init); 3438 3439 // If the previous declaration of VDecl was a tentative definition, 3440 // remove it from the set of tentative definitions. 3441 if (VDecl->getPreviousDeclaration() && 3442 VDecl->getPreviousDeclaration()->isTentativeDefinition(Context)) { 3443 bool Deleted = TentativeDefinitions.erase(VDecl->getDeclName()); 3444 assert(Deleted && "Unrecorded tentative definition?"); Deleted=Deleted; 3445 } 3446 3447 return; 3448} 3449 3450void Sema::ActOnUninitializedDecl(DeclPtrTy dcl, 3451 bool TypeContainsUndeducedAuto) { 3452 Decl *RealDecl = dcl.getAs<Decl>(); 3453 3454 // If there is no declaration, there was an error parsing it. Just ignore it. 3455 if (RealDecl == 0) 3456 return; 3457 3458 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 3459 QualType Type = Var->getType(); 3460 3461 // Record tentative definitions. 3462 if (Var->isTentativeDefinition(Context)) { 3463 std::pair<llvm::DenseMap<DeclarationName, VarDecl *>::iterator, bool> 3464 InsertPair = 3465 TentativeDefinitions.insert(std::make_pair(Var->getDeclName(), Var)); 3466 3467 // Keep the latest definition in the map. If we see 'int i; int i;' we 3468 // want the second one in the map. 3469 InsertPair.first->second = Var; 3470 3471 // However, for the list, we don't care about the order, just make sure 3472 // that there are no dupes for a given declaration name. 3473 if (InsertPair.second) 3474 TentativeDefinitionList.push_back(Var->getDeclName()); 3475 } 3476 3477 // C++ [dcl.init.ref]p3: 3478 // The initializer can be omitted for a reference only in a 3479 // parameter declaration (8.3.5), in the declaration of a 3480 // function return type, in the declaration of a class member 3481 // within its class declaration (9.2), and where the extern 3482 // specifier is explicitly used. 3483 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 3484 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 3485 << Var->getDeclName() 3486 << SourceRange(Var->getLocation(), Var->getLocation()); 3487 Var->setInvalidDecl(); 3488 return; 3489 } 3490 3491 // C++0x [dcl.spec.auto]p3 3492 if (TypeContainsUndeducedAuto) { 3493 Diag(Var->getLocation(), diag::err_auto_var_requires_init) 3494 << Var->getDeclName() << Type; 3495 Var->setInvalidDecl(); 3496 return; 3497 } 3498 3499 // An array without size is an incomplete type, and there are no special 3500 // rules in C++ to make such a definition acceptable. 3501 if (getLangOptions().CPlusPlus && Type->isIncompleteArrayType() && 3502 !Var->hasExternalStorage()) { 3503 Diag(Var->getLocation(), 3504 diag::err_typecheck_incomplete_array_needs_initializer); 3505 Var->setInvalidDecl(); 3506 return; 3507 } 3508 3509 // C++ [temp.expl.spec]p15: 3510 // An explicit specialization of a static data member of a template is a 3511 // definition if the declaration includes an initializer; otherwise, it 3512 // is a declaration. 3513 if (Var->isStaticDataMember() && 3514 Var->getInstantiatedFromStaticDataMember() && 3515 Var->getTemplateSpecializationKind() == TSK_ExplicitSpecialization) 3516 return; 3517 3518 // C++ [dcl.init]p9: 3519 // If no initializer is specified for an object, and the object 3520 // is of (possibly cv-qualified) non-POD class type (or array 3521 // thereof), the object shall be default-initialized; if the 3522 // object is of const-qualified type, the underlying class type 3523 // shall have a user-declared default constructor. 3524 // 3525 // FIXME: Diagnose the "user-declared default constructor" bit. 3526 if (getLangOptions().CPlusPlus) { 3527 QualType InitType = Type; 3528 if (const ArrayType *Array = Context.getAsArrayType(Type)) 3529 InitType = Context.getBaseElementType(Array); 3530 if ((!Var->hasExternalStorage() && !Var->isExternC()) && 3531 InitType->isRecordType() && !InitType->isDependentType()) { 3532 if (!RequireCompleteType(Var->getLocation(), InitType, 3533 diag::err_invalid_incomplete_type_use)) { 3534 ASTOwningVector<&ActionBase::DeleteExpr> ConstructorArgs(*this); 3535 3536 CXXConstructorDecl *Constructor 3537 = PerformInitializationByConstructor(InitType, 3538 MultiExprArg(*this, 0, 0), 3539 Var->getLocation(), 3540 SourceRange(Var->getLocation(), 3541 Var->getLocation()), 3542 Var->getDeclName(), 3543 IK_Default, 3544 ConstructorArgs); 3545 3546 // FIXME: Location info for the variable initialization? 3547 if (!Constructor) 3548 Var->setInvalidDecl(); 3549 else { 3550 // FIXME: Cope with initialization of arrays 3551 if (!Constructor->isTrivial() && 3552 InitializeVarWithConstructor(Var, Constructor, 3553 move_arg(ConstructorArgs))) 3554 Var->setInvalidDecl(); 3555 3556 FinalizeVarWithDestructor(Var, InitType); 3557 } 3558 } else { 3559 Var->setInvalidDecl(); 3560 } 3561 } 3562 } 3563 3564#if 0 3565 // FIXME: Temporarily disabled because we are not properly parsing 3566 // linkage specifications on declarations, e.g., 3567 // 3568 // extern "C" const CGPoint CGPointerZero; 3569 // 3570 // C++ [dcl.init]p9: 3571 // 3572 // If no initializer is specified for an object, and the 3573 // object is of (possibly cv-qualified) non-POD class type (or 3574 // array thereof), the object shall be default-initialized; if 3575 // the object is of const-qualified type, the underlying class 3576 // type shall have a user-declared default 3577 // constructor. Otherwise, if no initializer is specified for 3578 // an object, the object and its subobjects, if any, have an 3579 // indeterminate initial value; if the object or any of its 3580 // subobjects are of const-qualified type, the program is 3581 // ill-formed. 3582 // 3583 // This isn't technically an error in C, so we don't diagnose it. 3584 // 3585 // FIXME: Actually perform the POD/user-defined default 3586 // constructor check. 3587 if (getLangOptions().CPlusPlus && 3588 Context.getCanonicalType(Type).isConstQualified() && 3589 !Var->hasExternalStorage()) 3590 Diag(Var->getLocation(), diag::err_const_var_requires_init) 3591 << Var->getName() 3592 << SourceRange(Var->getLocation(), Var->getLocation()); 3593#endif 3594 } 3595} 3596 3597Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS, 3598 DeclPtrTy *Group, 3599 unsigned NumDecls) { 3600 llvm::SmallVector<Decl*, 8> Decls; 3601 3602 if (DS.isTypeSpecOwned()) 3603 Decls.push_back((Decl*)DS.getTypeRep()); 3604 3605 for (unsigned i = 0; i != NumDecls; ++i) 3606 if (Decl *D = Group[i].getAs<Decl>()) 3607 Decls.push_back(D); 3608 3609 // Perform semantic analysis that depends on having fully processed both 3610 // the declarator and initializer. 3611 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 3612 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 3613 if (!IDecl) 3614 continue; 3615 QualType T = IDecl->getType(); 3616 3617 // Block scope. C99 6.7p7: If an identifier for an object is declared with 3618 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 3619 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 3620 if (T->isDependentType()) { 3621 // If T is dependent, we should not require a complete type. 3622 // (RequireCompleteType shouldn't be called with dependent types.) 3623 // But we still can at least check if we've got an array of unspecified 3624 // size without an initializer. 3625 if (!IDecl->isInvalidDecl() && T->isIncompleteArrayType() && 3626 !IDecl->getInit()) { 3627 Diag(IDecl->getLocation(), diag::err_typecheck_decl_incomplete_type) 3628 << T; 3629 IDecl->setInvalidDecl(); 3630 } 3631 } else if (!IDecl->isInvalidDecl()) { 3632 // If T is an incomplete array type with an initializer list that is 3633 // dependent on something, its size has not been fixed. We could attempt 3634 // to fix the size for such arrays, but we would still have to check 3635 // here for initializers containing a C++0x vararg expansion, e.g. 3636 // template <typename... Args> void f(Args... args) { 3637 // int vals[] = { args }; 3638 // } 3639 const IncompleteArrayType *IAT = Context.getAsIncompleteArrayType(T); 3640 Expr *Init = IDecl->getInit(); 3641 if (IAT && Init && 3642 (Init->isTypeDependent() || Init->isValueDependent())) { 3643 // Check that the member type of the array is complete, at least. 3644 if (RequireCompleteType(IDecl->getLocation(), IAT->getElementType(), 3645 diag::err_typecheck_decl_incomplete_type)) 3646 IDecl->setInvalidDecl(); 3647 } else if (RequireCompleteType(IDecl->getLocation(), T, 3648 diag::err_typecheck_decl_incomplete_type)) 3649 IDecl->setInvalidDecl(); 3650 } 3651 } 3652 // File scope. C99 6.9.2p2: A declaration of an identifier for an 3653 // object that has file scope without an initializer, and without a 3654 // storage-class specifier or with the storage-class specifier "static", 3655 // constitutes a tentative definition. Note: A tentative definition with 3656 // external linkage is valid (C99 6.2.2p5). 3657 if (IDecl->isTentativeDefinition(Context) && !IDecl->isInvalidDecl()) { 3658 if (const IncompleteArrayType *ArrayT 3659 = Context.getAsIncompleteArrayType(T)) { 3660 if (RequireCompleteType(IDecl->getLocation(), 3661 ArrayT->getElementType(), 3662 diag::err_illegal_decl_array_incomplete_type)) 3663 IDecl->setInvalidDecl(); 3664 } else if (IDecl->getStorageClass() == VarDecl::Static) { 3665 // C99 6.9.2p3: If the declaration of an identifier for an object is 3666 // a tentative definition and has internal linkage (C99 6.2.2p3), the 3667 // declared type shall not be an incomplete type. 3668 // NOTE: code such as the following 3669 // static struct s; 3670 // struct s { int a; }; 3671 // is accepted by gcc. Hence here we issue a warning instead of 3672 // an error and we do not invalidate the static declaration. 3673 // NOTE: to avoid multiple warnings, only check the first declaration. 3674 if (IDecl->getPreviousDeclaration() == 0) 3675 RequireCompleteType(IDecl->getLocation(), T, 3676 diag::ext_typecheck_decl_incomplete_type); 3677 } 3678 } 3679 } 3680 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 3681 Decls.data(), Decls.size())); 3682} 3683 3684 3685/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 3686/// to introduce parameters into function prototype scope. 3687Sema::DeclPtrTy 3688Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 3689 const DeclSpec &DS = D.getDeclSpec(); 3690 3691 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 3692 VarDecl::StorageClass StorageClass = VarDecl::None; 3693 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 3694 StorageClass = VarDecl::Register; 3695 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 3696 Diag(DS.getStorageClassSpecLoc(), 3697 diag::err_invalid_storage_class_in_func_decl); 3698 D.getMutableDeclSpec().ClearStorageClassSpecs(); 3699 } 3700 3701 if (D.getDeclSpec().isThreadSpecified()) 3702 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 3703 3704 DiagnoseFunctionSpecifiers(D); 3705 3706 // Check that there are no default arguments inside the type of this 3707 // parameter (C++ only). 3708 if (getLangOptions().CPlusPlus) 3709 CheckExtraCXXDefaultArguments(D); 3710 3711 DeclaratorInfo *DInfo = 0; 3712 TagDecl *OwnedDecl = 0; 3713 QualType parmDeclType = GetTypeForDeclarator(D, S, &DInfo, &OwnedDecl); 3714 3715 if (getLangOptions().CPlusPlus && OwnedDecl && OwnedDecl->isDefinition()) { 3716 // C++ [dcl.fct]p6: 3717 // Types shall not be defined in return or parameter types. 3718 Diag(OwnedDecl->getLocation(), diag::err_type_defined_in_param_type) 3719 << Context.getTypeDeclType(OwnedDecl); 3720 } 3721 3722 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 3723 // Can this happen for params? We already checked that they don't conflict 3724 // among each other. Here they can only shadow globals, which is ok. 3725 IdentifierInfo *II = D.getIdentifier(); 3726 if (II) { 3727 if (NamedDecl *PrevDecl = LookupSingleName(S, II, LookupOrdinaryName)) { 3728 if (PrevDecl->isTemplateParameter()) { 3729 // Maybe we will complain about the shadowed template parameter. 3730 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 3731 // Just pretend that we didn't see the previous declaration. 3732 PrevDecl = 0; 3733 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 3734 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 3735 3736 // Recover by removing the name 3737 II = 0; 3738 D.SetIdentifier(0, D.getIdentifierLoc()); 3739 } 3740 } 3741 } 3742 3743 // Parameters can not be abstract class types. 3744 // For record types, this is done by the AbstractClassUsageDiagnoser once 3745 // the class has been completely parsed. 3746 if (!CurContext->isRecord() && 3747 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 3748 diag::err_abstract_type_in_decl, 3749 AbstractParamType)) 3750 D.setInvalidType(true); 3751 3752 QualType T = adjustParameterType(parmDeclType); 3753 3754 ParmVarDecl *New 3755 = ParmVarDecl::Create(Context, CurContext, D.getIdentifierLoc(), II, 3756 T, DInfo, StorageClass, 0); 3757 3758 if (D.isInvalidType()) 3759 New->setInvalidDecl(); 3760 3761 // Parameter declarators cannot be interface types. All ObjC objects are 3762 // passed by reference. 3763 if (T->isObjCInterfaceType()) { 3764 Diag(D.getIdentifierLoc(), 3765 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 3766 New->setInvalidDecl(); 3767 } 3768 3769 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 3770 if (D.getCXXScopeSpec().isSet()) { 3771 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 3772 << D.getCXXScopeSpec().getRange(); 3773 New->setInvalidDecl(); 3774 } 3775 3776 // ISO/IEC TR 18037 S6.7.3: "The type of an object with automatic storage 3777 // duration shall not be qualified by an address-space qualifier." 3778 // Since all parameters have automatic store duration, they can not have 3779 // an address space. 3780 if (T.getAddressSpace() != 0) { 3781 Diag(D.getIdentifierLoc(), 3782 diag::err_arg_with_address_space); 3783 New->setInvalidDecl(); 3784 } 3785 3786 3787 // Add the parameter declaration into this scope. 3788 S->AddDecl(DeclPtrTy::make(New)); 3789 if (II) 3790 IdResolver.AddDecl(New); 3791 3792 ProcessDeclAttributes(S, New, D); 3793 3794 if (New->hasAttr<BlocksAttr>()) { 3795 Diag(New->getLocation(), diag::err_block_on_nonlocal); 3796 } 3797 return DeclPtrTy::make(New); 3798} 3799 3800void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 3801 SourceLocation LocAfterDecls) { 3802 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3803 "Not a function declarator!"); 3804 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3805 3806 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 3807 // for a K&R function. 3808 if (!FTI.hasPrototype) { 3809 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 3810 --i; 3811 if (FTI.ArgInfo[i].Param == 0) { 3812 llvm::SmallString<256> Code; 3813 llvm::raw_svector_ostream(Code) << " int " 3814 << FTI.ArgInfo[i].Ident->getName() 3815 << ";\n"; 3816 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 3817 << FTI.ArgInfo[i].Ident 3818 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code.str()); 3819 3820 // Implicitly declare the argument as type 'int' for lack of a better 3821 // type. 3822 DeclSpec DS; 3823 const char* PrevSpec; // unused 3824 unsigned DiagID; // unused 3825 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 3826 PrevSpec, DiagID); 3827 Declarator ParamD(DS, Declarator::KNRTypeListContext); 3828 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 3829 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 3830 } 3831 } 3832 } 3833} 3834 3835Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 3836 Declarator &D) { 3837 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 3838 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 3839 "Not a function declarator!"); 3840 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 3841 3842 if (FTI.hasPrototype) { 3843 // FIXME: Diagnose arguments without names in C. 3844 } 3845 3846 Scope *ParentScope = FnBodyScope->getParent(); 3847 3848 DeclPtrTy DP = HandleDeclarator(ParentScope, D, 3849 MultiTemplateParamsArg(*this), 3850 /*IsFunctionDefinition=*/true); 3851 return ActOnStartOfFunctionDef(FnBodyScope, DP); 3852} 3853 3854Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 3855 // Clear the last template instantiation error context. 3856 LastTemplateInstantiationErrorContext = ActiveTemplateInstantiation(); 3857 3858 if (!D) 3859 return D; 3860 FunctionDecl *FD = 0; 3861 3862 if (FunctionTemplateDecl *FunTmpl 3863 = dyn_cast<FunctionTemplateDecl>(D.getAs<Decl>())) 3864 FD = FunTmpl->getTemplatedDecl(); 3865 else 3866 FD = cast<FunctionDecl>(D.getAs<Decl>()); 3867 3868 CurFunctionNeedsScopeChecking = false; 3869 3870 // See if this is a redefinition. 3871 const FunctionDecl *Definition; 3872 if (FD->getBody(Definition)) { 3873 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 3874 Diag(Definition->getLocation(), diag::note_previous_definition); 3875 } 3876 3877 // Builtin functions cannot be defined. 3878 if (unsigned BuiltinID = FD->getBuiltinID()) { 3879 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 3880 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 3881 FD->setInvalidDecl(); 3882 } 3883 } 3884 3885 // The return type of a function definition must be complete 3886 // (C99 6.9.1p3, C++ [dcl.fct]p6). 3887 QualType ResultType = FD->getResultType(); 3888 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 3889 !FD->isInvalidDecl() && 3890 RequireCompleteType(FD->getLocation(), ResultType, 3891 diag::err_func_def_incomplete_result)) 3892 FD->setInvalidDecl(); 3893 3894 // GNU warning -Wmissing-prototypes: 3895 // Warn if a global function is defined without a previous 3896 // prototype declaration. This warning is issued even if the 3897 // definition itself provides a prototype. The aim is to detect 3898 // global functions that fail to be declared in header files. 3899 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 3900 !FD->isMain()) { 3901 bool MissingPrototype = true; 3902 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 3903 Prev; Prev = Prev->getPreviousDeclaration()) { 3904 // Ignore any declarations that occur in function or method 3905 // scope, because they aren't visible from the header. 3906 if (Prev->getDeclContext()->isFunctionOrMethod()) 3907 continue; 3908 3909 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 3910 break; 3911 } 3912 3913 if (MissingPrototype) 3914 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 3915 } 3916 3917 if (FnBodyScope) 3918 PushDeclContext(FnBodyScope, FD); 3919 3920 // Check the validity of our function parameters 3921 CheckParmsForFunctionDef(FD); 3922 3923 // Introduce our parameters into the function scope 3924 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 3925 ParmVarDecl *Param = FD->getParamDecl(p); 3926 Param->setOwningFunction(FD); 3927 3928 // If this has an identifier, add it to the scope stack. 3929 if (Param->getIdentifier() && FnBodyScope) 3930 PushOnScopeChains(Param, FnBodyScope); 3931 } 3932 3933 // Checking attributes of current function definition 3934 // dllimport attribute. 3935 if (FD->getAttr<DLLImportAttr>() && 3936 (!FD->getAttr<DLLExportAttr>())) { 3937 // dllimport attribute cannot be applied to definition. 3938 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 3939 Diag(FD->getLocation(), 3940 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 3941 << "dllimport"; 3942 FD->setInvalidDecl(); 3943 return DeclPtrTy::make(FD); 3944 } else { 3945 // If a symbol previously declared dllimport is later defined, the 3946 // attribute is ignored in subsequent references, and a warning is 3947 // emitted. 3948 Diag(FD->getLocation(), 3949 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 3950 << FD->getNameAsCString() << "dllimport"; 3951 } 3952 } 3953 return DeclPtrTy::make(FD); 3954} 3955 3956Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 3957 return ActOnFinishFunctionBody(D, move(BodyArg), false); 3958} 3959 3960Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg, 3961 bool IsInstantiation) { 3962 Decl *dcl = D.getAs<Decl>(); 3963 Stmt *Body = BodyArg.takeAs<Stmt>(); 3964 3965 FunctionDecl *FD = 0; 3966 FunctionTemplateDecl *FunTmpl = dyn_cast_or_null<FunctionTemplateDecl>(dcl); 3967 if (FunTmpl) 3968 FD = FunTmpl->getTemplatedDecl(); 3969 else 3970 FD = dyn_cast_or_null<FunctionDecl>(dcl); 3971 3972 if (FD) { 3973 FD->setBody(Body); 3974 if (FD->isMain()) 3975 // C and C++ allow for main to automagically return 0. 3976 // Implements C++ [basic.start.main]p5 and C99 5.1.2.2.3. 3977 FD->setHasImplicitReturnZero(true); 3978 else 3979 CheckFallThroughForFunctionDef(FD, Body); 3980 3981 if (!FD->isInvalidDecl()) 3982 DiagnoseUnusedParameters(FD->param_begin(), FD->param_end()); 3983 3984 // C++ [basic.def.odr]p2: 3985 // [...] A virtual member function is used if it is not pure. [...] 3986 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD)) 3987 if (Method->isVirtual() && !Method->isPure()) 3988 MarkDeclarationReferenced(Method->getLocation(), Method); 3989 3990 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 3991 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 3992 assert(MD == getCurMethodDecl() && "Method parsing confused"); 3993 MD->setBody(Body); 3994 CheckFallThroughForFunctionDef(MD, Body); 3995 MD->setEndLoc(Body->getLocEnd()); 3996 3997 if (!MD->isInvalidDecl()) 3998 DiagnoseUnusedParameters(MD->param_begin(), MD->param_end()); 3999 } else { 4000 Body->Destroy(Context); 4001 return DeclPtrTy(); 4002 } 4003 if (!IsInstantiation) 4004 PopDeclContext(); 4005 4006 // Verify and clean out per-function state. 4007 4008 assert(&getLabelMap() == &FunctionLabelMap && "Didn't pop block right?"); 4009 4010 // Check goto/label use. 4011 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 4012 I = FunctionLabelMap.begin(), E = FunctionLabelMap.end(); I != E; ++I) { 4013 LabelStmt *L = I->second; 4014 4015 // Verify that we have no forward references left. If so, there was a goto 4016 // or address of a label taken, but no definition of it. Label fwd 4017 // definitions are indicated with a null substmt. 4018 if (L->getSubStmt() != 0) 4019 continue; 4020 4021 // Emit error. 4022 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 4023 4024 // At this point, we have gotos that use the bogus label. Stitch it into 4025 // the function body so that they aren't leaked and that the AST is well 4026 // formed. 4027 if (Body == 0) { 4028 // The whole function wasn't parsed correctly, just delete this. 4029 L->Destroy(Context); 4030 continue; 4031 } 4032 4033 // Otherwise, the body is valid: we want to stitch the label decl into the 4034 // function somewhere so that it is properly owned and so that the goto 4035 // has a valid target. Do this by creating a new compound stmt with the 4036 // label in it. 4037 4038 // Give the label a sub-statement. 4039 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 4040 4041 CompoundStmt *Compound = isa<CXXTryStmt>(Body) ? 4042 cast<CXXTryStmt>(Body)->getTryBlock() : 4043 cast<CompoundStmt>(Body); 4044 std::vector<Stmt*> Elements(Compound->body_begin(), Compound->body_end()); 4045 Elements.push_back(L); 4046 Compound->setStmts(Context, &Elements[0], Elements.size()); 4047 } 4048 FunctionLabelMap.clear(); 4049 4050 if (!Body) return D; 4051 4052 // Verify that that gotos and switch cases don't jump into scopes illegally. 4053 if (CurFunctionNeedsScopeChecking) 4054 DiagnoseInvalidJumps(Body); 4055 4056 // C++ constructors that have function-try-blocks can't have return 4057 // statements in the handlers of that block. (C++ [except.handle]p14) 4058 // Verify this. 4059 if (FD && isa<CXXConstructorDecl>(FD) && isa<CXXTryStmt>(Body)) 4060 DiagnoseReturnInConstructorExceptionHandler(cast<CXXTryStmt>(Body)); 4061 4062 if (CXXDestructorDecl *Destructor = dyn_cast<CXXDestructorDecl>(dcl)) 4063 MarkBaseAndMemberDestructorsReferenced(Destructor); 4064 4065 // If any errors have occurred, clear out any temporaries that may have 4066 // been leftover. This ensures that these temporaries won't be picked up for 4067 // deletion in some later function. 4068 if (PP.getDiagnostics().hasErrorOccurred()) 4069 ExprTemporaries.clear(); 4070 4071 assert(ExprTemporaries.empty() && "Leftover temporaries in function"); 4072 return D; 4073} 4074 4075/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 4076/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 4077NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 4078 IdentifierInfo &II, Scope *S) { 4079 // Before we produce a declaration for an implicitly defined 4080 // function, see whether there was a locally-scoped declaration of 4081 // this name as a function or variable. If so, use that 4082 // (non-visible) declaration, and complain about it. 4083 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 4084 = LocallyScopedExternalDecls.find(&II); 4085 if (Pos != LocallyScopedExternalDecls.end()) { 4086 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 4087 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 4088 return Pos->second; 4089 } 4090 4091 // Extension in C99. Legal in C90, but warn about it. 4092 if (II.getName().startswith("__builtin_")) 4093 Diag(Loc, diag::warn_builtin_unknown) << &II; 4094 else if (getLangOptions().C99) 4095 Diag(Loc, diag::ext_implicit_function_decl) << &II; 4096 else 4097 Diag(Loc, diag::warn_implicit_function_decl) << &II; 4098 4099 // Set a Declarator for the implicit definition: int foo(); 4100 const char *Dummy; 4101 DeclSpec DS; 4102 unsigned DiagID; 4103 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy, DiagID); 4104 Error = Error; // Silence warning. 4105 assert(!Error && "Error setting up implicit decl!"); 4106 Declarator D(DS, Declarator::BlockContext); 4107 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 0, 4108 0, 0, false, SourceLocation(), 4109 false, 0,0,0, Loc, Loc, D), 4110 SourceLocation()); 4111 D.SetIdentifier(&II, Loc); 4112 4113 // Insert this function into translation-unit scope. 4114 4115 DeclContext *PrevDC = CurContext; 4116 CurContext = Context.getTranslationUnitDecl(); 4117 4118 FunctionDecl *FD = 4119 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D).getAs<Decl>()); 4120 FD->setImplicit(); 4121 4122 CurContext = PrevDC; 4123 4124 AddKnownFunctionAttributes(FD); 4125 4126 return FD; 4127} 4128 4129/// \brief Adds any function attributes that we know a priori based on 4130/// the declaration of this function. 4131/// 4132/// These attributes can apply both to implicitly-declared builtins 4133/// (like __builtin___printf_chk) or to library-declared functions 4134/// like NSLog or printf. 4135void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 4136 if (FD->isInvalidDecl()) 4137 return; 4138 4139 // If this is a built-in function, map its builtin attributes to 4140 // actual attributes. 4141 if (unsigned BuiltinID = FD->getBuiltinID()) { 4142 // Handle printf-formatting attributes. 4143 unsigned FormatIdx; 4144 bool HasVAListArg; 4145 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 4146 if (!FD->getAttr<FormatAttr>()) 4147 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 4148 HasVAListArg ? 0 : FormatIdx + 2)); 4149 } 4150 4151 // Mark const if we don't care about errno and that is the only 4152 // thing preventing the function from being const. This allows 4153 // IRgen to use LLVM intrinsics for such functions. 4154 if (!getLangOptions().MathErrno && 4155 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 4156 if (!FD->getAttr<ConstAttr>()) 4157 FD->addAttr(::new (Context) ConstAttr()); 4158 } 4159 4160 if (Context.BuiltinInfo.isNoReturn(BuiltinID)) 4161 FD->addAttr(::new (Context) NoReturnAttr()); 4162 } 4163 4164 IdentifierInfo *Name = FD->getIdentifier(); 4165 if (!Name) 4166 return; 4167 if ((!getLangOptions().CPlusPlus && 4168 FD->getDeclContext()->isTranslationUnit()) || 4169 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 4170 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 4171 LinkageSpecDecl::lang_c)) { 4172 // Okay: this could be a libc/libm/Objective-C function we know 4173 // about. 4174 } else 4175 return; 4176 4177 if (Name->isStr("NSLog") || Name->isStr("NSLogv")) { 4178 // FIXME: NSLog and NSLogv should be target specific 4179 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 4180 // FIXME: We known better than our headers. 4181 const_cast<FormatAttr *>(Format)->setType("printf"); 4182 } else 4183 FD->addAttr(::new (Context) FormatAttr("printf", 1, 4184 Name->isStr("NSLogv") ? 0 : 2)); 4185 } else if (Name->isStr("asprintf") || Name->isStr("vasprintf")) { 4186 // FIXME: asprintf and vasprintf aren't C99 functions. Should they be 4187 // target-specific builtins, perhaps? 4188 if (!FD->getAttr<FormatAttr>()) 4189 FD->addAttr(::new (Context) FormatAttr("printf", 2, 4190 Name->isStr("vasprintf") ? 0 : 3)); 4191 } 4192} 4193 4194TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T, 4195 DeclaratorInfo *DInfo) { 4196 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 4197 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 4198 4199 if (!DInfo) { 4200 assert(D.isInvalidType() && "no declarator info for valid type"); 4201 DInfo = Context.getTrivialDeclaratorInfo(T); 4202 } 4203 4204 // Scope manipulation handled by caller. 4205 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 4206 D.getIdentifierLoc(), 4207 D.getIdentifier(), 4208 DInfo); 4209 4210 if (const TagType *TT = T->getAs<TagType>()) { 4211 TagDecl *TD = TT->getDecl(); 4212 4213 // If the TagDecl that the TypedefDecl points to is an anonymous decl 4214 // keep track of the TypedefDecl. 4215 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 4216 TD->setTypedefForAnonDecl(NewTD); 4217 } 4218 4219 if (D.isInvalidType()) 4220 NewTD->setInvalidDecl(); 4221 return NewTD; 4222} 4223 4224 4225/// \brief Determine whether a tag with a given kind is acceptable 4226/// as a redeclaration of the given tag declaration. 4227/// 4228/// \returns true if the new tag kind is acceptable, false otherwise. 4229bool Sema::isAcceptableTagRedeclaration(const TagDecl *Previous, 4230 TagDecl::TagKind NewTag, 4231 SourceLocation NewTagLoc, 4232 const IdentifierInfo &Name) { 4233 // C++ [dcl.type.elab]p3: 4234 // The class-key or enum keyword present in the 4235 // elaborated-type-specifier shall agree in kind with the 4236 // declaration to which the name in theelaborated-type-specifier 4237 // refers. This rule also applies to the form of 4238 // elaborated-type-specifier that declares a class-name or 4239 // friend class since it can be construed as referring to the 4240 // definition of the class. Thus, in any 4241 // elaborated-type-specifier, the enum keyword shall be used to 4242 // refer to an enumeration (7.2), the union class-keyshall be 4243 // used to refer to a union (clause 9), and either the class or 4244 // struct class-key shall be used to refer to a class (clause 9) 4245 // declared using the class or struct class-key. 4246 TagDecl::TagKind OldTag = Previous->getTagKind(); 4247 if (OldTag == NewTag) 4248 return true; 4249 4250 if ((OldTag == TagDecl::TK_struct || OldTag == TagDecl::TK_class) && 4251 (NewTag == TagDecl::TK_struct || NewTag == TagDecl::TK_class)) { 4252 // Warn about the struct/class tag mismatch. 4253 bool isTemplate = false; 4254 if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Previous)) 4255 isTemplate = Record->getDescribedClassTemplate(); 4256 4257 Diag(NewTagLoc, diag::warn_struct_class_tag_mismatch) 4258 << (NewTag == TagDecl::TK_class) 4259 << isTemplate << &Name 4260 << CodeModificationHint::CreateReplacement(SourceRange(NewTagLoc), 4261 OldTag == TagDecl::TK_class? "class" : "struct"); 4262 Diag(Previous->getLocation(), diag::note_previous_use); 4263 return true; 4264 } 4265 return false; 4266} 4267 4268/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 4269/// former case, Name will be non-null. In the later case, Name will be null. 4270/// TagSpec indicates what kind of tag this is. TUK indicates whether this is a 4271/// reference/declaration/definition of a tag. 4272Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK, 4273 SourceLocation KWLoc, const CXXScopeSpec &SS, 4274 IdentifierInfo *Name, SourceLocation NameLoc, 4275 AttributeList *Attr, AccessSpecifier AS, 4276 MultiTemplateParamsArg TemplateParameterLists, 4277 bool &OwnedDecl, bool &IsDependent) { 4278 // If this is not a definition, it must have a name. 4279 assert((Name != 0 || TUK == TUK_Definition) && 4280 "Nameless record must be a definition!"); 4281 4282 OwnedDecl = false; 4283 TagDecl::TagKind Kind = TagDecl::getTagKindForTypeSpec(TagSpec); 4284 4285 // FIXME: Check explicit specializations more carefully. 4286 bool isExplicitSpecialization = false; 4287 if (TUK != TUK_Reference) { 4288 if (TemplateParameterList *TemplateParams 4289 = MatchTemplateParametersToScopeSpecifier(KWLoc, SS, 4290 (TemplateParameterList**)TemplateParameterLists.get(), 4291 TemplateParameterLists.size(), 4292 isExplicitSpecialization)) { 4293 if (TemplateParams->size() > 0) { 4294 // This is a declaration or definition of a class template (which may 4295 // be a member of another template). 4296 OwnedDecl = false; 4297 DeclResult Result = CheckClassTemplate(S, TagSpec, TUK, KWLoc, 4298 SS, Name, NameLoc, Attr, 4299 TemplateParams, 4300 AS); 4301 TemplateParameterLists.release(); 4302 return Result.get(); 4303 } else { 4304 // The "template<>" header is extraneous. 4305 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams) 4306 << ElaboratedType::getNameForTagKind(Kind) << Name; 4307 isExplicitSpecialization = true; 4308 } 4309 } 4310 4311 TemplateParameterLists.release(); 4312 } 4313 4314 DeclContext *SearchDC = CurContext; 4315 DeclContext *DC = CurContext; 4316 NamedDecl *PrevDecl = 0; 4317 bool isStdBadAlloc = false; 4318 bool Invalid = false; 4319 4320 RedeclarationKind Redecl = (RedeclarationKind) (TUK != TUK_Reference); 4321 4322 if (Name && SS.isNotEmpty()) { 4323 // We have a nested-name tag ('struct foo::bar'). 4324 4325 // Check for invalid 'foo::'. 4326 if (SS.isInvalid()) { 4327 Name = 0; 4328 goto CreateNewDecl; 4329 } 4330 4331 // If this is a friend or a reference to a class in a dependent 4332 // context, don't try to make a decl for it. 4333 if (TUK == TUK_Friend || TUK == TUK_Reference) { 4334 DC = computeDeclContext(SS, false); 4335 if (!DC) { 4336 IsDependent = true; 4337 return DeclPtrTy(); 4338 } 4339 } 4340 4341 if (RequireCompleteDeclContext(SS)) 4342 return DeclPtrTy::make((Decl *)0); 4343 4344 DC = computeDeclContext(SS, true); 4345 SearchDC = DC; 4346 // Look-up name inside 'foo::'. 4347 LookupResult R(*this, Name, NameLoc, LookupTagName, Redecl); 4348 LookupQualifiedName(R, DC); 4349 4350 if (R.isAmbiguous()) 4351 return DeclPtrTy(); 4352 4353 if (R.getResultKind() == LookupResult::Found) 4354 PrevDecl = dyn_cast<TagDecl>(R.getFoundDecl()); 4355 4356 // A tag 'foo::bar' must already exist. 4357 if (!PrevDecl) { 4358 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 4359 Name = 0; 4360 Invalid = true; 4361 goto CreateNewDecl; 4362 } 4363 } else if (Name) { 4364 // If this is a named struct, check to see if there was a previous forward 4365 // declaration or definition. 4366 // FIXME: We're looking into outer scopes here, even when we 4367 // shouldn't be. Doing so can result in ambiguities that we 4368 // shouldn't be diagnosing. 4369 LookupResult R(*this, Name, NameLoc, LookupTagName, Redecl); 4370 LookupName(R, S); 4371 if (R.isAmbiguous()) { 4372 // FIXME: This is not best way to recover from case like: 4373 // 4374 // struct S s; 4375 // 4376 // causes needless "incomplete type" error later. 4377 Name = 0; 4378 PrevDecl = 0; 4379 Invalid = true; 4380 } else 4381 PrevDecl = R.getAsSingleDecl(Context); 4382 4383 if (!getLangOptions().CPlusPlus && TUK != TUK_Reference) { 4384 // FIXME: This makes sure that we ignore the contexts associated 4385 // with C structs, unions, and enums when looking for a matching 4386 // tag declaration or definition. See the similar lookup tweak 4387 // in Sema::LookupName; is there a better way to deal with this? 4388 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 4389 SearchDC = SearchDC->getParent(); 4390 } 4391 } 4392 4393 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4394 // Maybe we will complain about the shadowed template parameter. 4395 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 4396 // Just pretend that we didn't see the previous declaration. 4397 PrevDecl = 0; 4398 } 4399 4400 if (getLangOptions().CPlusPlus && Name && DC && StdNamespace && 4401 DC->Equals(StdNamespace) && Name->isStr("bad_alloc")) { 4402 // This is a declaration of or a reference to "std::bad_alloc". 4403 isStdBadAlloc = true; 4404 4405 if (!PrevDecl && StdBadAlloc) { 4406 // std::bad_alloc has been implicitly declared (but made invisible to 4407 // name lookup). Fill in this implicit declaration as the previous 4408 // declaration, so that the declarations get chained appropriately. 4409 PrevDecl = StdBadAlloc; 4410 } 4411 } 4412 4413 if (PrevDecl) { 4414 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 4415 // If this is a use of a previous tag, or if the tag is already declared 4416 // in the same scope (so that the definition/declaration completes or 4417 // rementions the tag), reuse the decl. 4418 if (TUK == TUK_Reference || TUK == TUK_Friend || 4419 isDeclInScope(PrevDecl, SearchDC, S)) { 4420 // Make sure that this wasn't declared as an enum and now used as a 4421 // struct or something similar. 4422 if (!isAcceptableTagRedeclaration(PrevTagDecl, Kind, KWLoc, *Name)) { 4423 bool SafeToContinue 4424 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 4425 Kind != TagDecl::TK_enum); 4426 if (SafeToContinue) 4427 Diag(KWLoc, diag::err_use_with_wrong_tag) 4428 << Name 4429 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 4430 PrevTagDecl->getKindName()); 4431 else 4432 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 4433 Diag(PrevDecl->getLocation(), diag::note_previous_use); 4434 4435 if (SafeToContinue) 4436 Kind = PrevTagDecl->getTagKind(); 4437 else { 4438 // Recover by making this an anonymous redefinition. 4439 Name = 0; 4440 PrevDecl = 0; 4441 Invalid = true; 4442 } 4443 } 4444 4445 if (!Invalid) { 4446 // If this is a use, just return the declaration we found. 4447 4448 // FIXME: In the future, return a variant or some other clue 4449 // for the consumer of this Decl to know it doesn't own it. 4450 // For our current ASTs this shouldn't be a problem, but will 4451 // need to be changed with DeclGroups. 4452 if (TUK == TUK_Reference || TUK == TUK_Friend) 4453 return DeclPtrTy::make(PrevDecl); 4454 4455 // Diagnose attempts to redefine a tag. 4456 if (TUK == TUK_Definition) { 4457 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 4458 // If we're defining a specialization and the previous definition 4459 // is from an implicit instantiation, don't emit an error 4460 // here; we'll catch this in the general case below. 4461 if (!isExplicitSpecialization || 4462 !isa<CXXRecordDecl>(Def) || 4463 cast<CXXRecordDecl>(Def)->getTemplateSpecializationKind() 4464 == TSK_ExplicitSpecialization) { 4465 Diag(NameLoc, diag::err_redefinition) << Name; 4466 Diag(Def->getLocation(), diag::note_previous_definition); 4467 // If this is a redefinition, recover by making this 4468 // struct be anonymous, which will make any later 4469 // references get the previous definition. 4470 Name = 0; 4471 PrevDecl = 0; 4472 Invalid = true; 4473 } 4474 } else { 4475 // If the type is currently being defined, complain 4476 // about a nested redefinition. 4477 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 4478 if (Tag->isBeingDefined()) { 4479 Diag(NameLoc, diag::err_nested_redefinition) << Name; 4480 Diag(PrevTagDecl->getLocation(), 4481 diag::note_previous_definition); 4482 Name = 0; 4483 PrevDecl = 0; 4484 Invalid = true; 4485 } 4486 } 4487 4488 // Okay, this is definition of a previously declared or referenced 4489 // tag PrevDecl. We're going to create a new Decl for it. 4490 } 4491 } 4492 // If we get here we have (another) forward declaration or we 4493 // have a definition. Just create a new decl. 4494 4495 } else { 4496 // If we get here, this is a definition of a new tag type in a nested 4497 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 4498 // new decl/type. We set PrevDecl to NULL so that the entities 4499 // have distinct types. 4500 PrevDecl = 0; 4501 } 4502 // If we get here, we're going to create a new Decl. If PrevDecl 4503 // is non-NULL, it's a definition of the tag declared by 4504 // PrevDecl. If it's NULL, we have a new definition. 4505 } else { 4506 // PrevDecl is a namespace, template, or anything else 4507 // that lives in the IDNS_Tag identifier namespace. 4508 if (isDeclInScope(PrevDecl, SearchDC, S)) { 4509 // The tag name clashes with a namespace name, issue an error and 4510 // recover by making this tag be anonymous. 4511 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 4512 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4513 Name = 0; 4514 PrevDecl = 0; 4515 Invalid = true; 4516 } else { 4517 // The existing declaration isn't relevant to us; we're in a 4518 // new scope, so clear out the previous declaration. 4519 PrevDecl = 0; 4520 } 4521 } 4522 } else if (TUK == TUK_Reference && SS.isEmpty() && Name && 4523 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 4524 // C++ [basic.scope.pdecl]p5: 4525 // -- for an elaborated-type-specifier of the form 4526 // 4527 // class-key identifier 4528 // 4529 // if the elaborated-type-specifier is used in the 4530 // decl-specifier-seq or parameter-declaration-clause of a 4531 // function defined in namespace scope, the identifier is 4532 // declared as a class-name in the namespace that contains 4533 // the declaration; otherwise, except as a friend 4534 // declaration, the identifier is declared in the smallest 4535 // non-class, non-function-prototype scope that contains the 4536 // declaration. 4537 // 4538 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 4539 // C structs and unions. 4540 // 4541 // GNU C also supports this behavior as part of its incomplete 4542 // enum types extension, while GNU C++ does not. 4543 // 4544 // Find the context where we'll be declaring the tag. 4545 // FIXME: We would like to maintain the current DeclContext as the 4546 // lexical context, 4547 while (SearchDC->isRecord()) 4548 SearchDC = SearchDC->getParent(); 4549 4550 // Find the scope where we'll be declaring the tag. 4551 while (S->isClassScope() || 4552 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 4553 ((S->getFlags() & Scope::DeclScope) == 0) || 4554 (S->getEntity() && 4555 ((DeclContext *)S->getEntity())->isTransparentContext())) 4556 S = S->getParent(); 4557 4558 } else if (TUK == TUK_Friend && SS.isEmpty() && Name) { 4559 // C++ [namespace.memdef]p3: 4560 // If a friend declaration in a non-local class first declares a 4561 // class or function, the friend class or function is a member of 4562 // the innermost enclosing namespace. 4563 while (!SearchDC->isFileContext()) 4564 SearchDC = SearchDC->getParent(); 4565 4566 // The entity of a decl scope is a DeclContext; see PushDeclContext. 4567 while (S->getEntity() != SearchDC) 4568 S = S->getParent(); 4569 } 4570 4571CreateNewDecl: 4572 4573 // If there is an identifier, use the location of the identifier as the 4574 // location of the decl, otherwise use the location of the struct/union 4575 // keyword. 4576 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 4577 4578 // Otherwise, create a new declaration. If there is a previous 4579 // declaration of the same entity, the two will be linked via 4580 // PrevDecl. 4581 TagDecl *New; 4582 4583 if (Kind == TagDecl::TK_enum) { 4584 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4585 // enum X { A, B, C } D; D should chain to X. 4586 New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc, 4587 cast_or_null<EnumDecl>(PrevDecl)); 4588 // If this is an undefined enum, warn. 4589 if (TUK != TUK_Definition && !Invalid) { 4590 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 4591 : diag::ext_forward_ref_enum; 4592 Diag(Loc, DK); 4593 } 4594 } else { 4595 // struct/union/class 4596 4597 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 4598 // struct X { int A; } D; D should chain to X. 4599 if (getLangOptions().CPlusPlus) { 4600 // FIXME: Look for a way to use RecordDecl for simple structs. 4601 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4602 cast_or_null<CXXRecordDecl>(PrevDecl)); 4603 4604 if (isStdBadAlloc && (!StdBadAlloc || StdBadAlloc->isImplicit())) 4605 StdBadAlloc = cast<CXXRecordDecl>(New); 4606 } else 4607 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, KWLoc, 4608 cast_or_null<RecordDecl>(PrevDecl)); 4609 } 4610 4611 if (Kind != TagDecl::TK_enum) { 4612 // Handle #pragma pack: if the #pragma pack stack has non-default 4613 // alignment, make up a packed attribute for this decl. These 4614 // attributes are checked when the ASTContext lays out the 4615 // structure. 4616 // 4617 // It is important for implementing the correct semantics that this 4618 // happen here (in act on tag decl). The #pragma pack stack is 4619 // maintained as a result of parser callbacks which can occur at 4620 // many points during the parsing of a struct declaration (because 4621 // the #pragma tokens are effectively skipped over during the 4622 // parsing of the struct). 4623 if (unsigned Alignment = getPragmaPackAlignment()) 4624 New->addAttr(::new (Context) PragmaPackAttr(Alignment * 8)); 4625 } 4626 4627 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 4628 // C++ [dcl.typedef]p3: 4629 // [...] Similarly, in a given scope, a class or enumeration 4630 // shall not be declared with the same name as a typedef-name 4631 // that is declared in that scope and refers to a type other 4632 // than the class or enumeration itself. 4633 LookupResult Lookup(*this, Name, NameLoc, LookupOrdinaryName, 4634 ForRedeclaration); 4635 LookupName(Lookup, S); 4636 TypedefDecl *PrevTypedef = 0; 4637 if (NamedDecl *Prev = Lookup.getAsSingleDecl(Context)) 4638 PrevTypedef = dyn_cast<TypedefDecl>(Prev); 4639 4640 NamedDecl *PrevTypedefNamed = PrevTypedef; 4641 if (PrevTypedef && isDeclInScope(PrevTypedefNamed, SearchDC, S) && 4642 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 4643 Context.getCanonicalType(Context.getTypeDeclType(New))) { 4644 Diag(Loc, diag::err_tag_definition_of_typedef) 4645 << Context.getTypeDeclType(New) 4646 << PrevTypedef->getUnderlyingType(); 4647 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 4648 Invalid = true; 4649 } 4650 } 4651 4652 // If this is a specialization of a member class (of a class template), 4653 // check the specialization. 4654 if (isExplicitSpecialization && CheckMemberSpecialization(New, PrevDecl)) 4655 Invalid = true; 4656 4657 if (Invalid) 4658 New->setInvalidDecl(); 4659 4660 if (Attr) 4661 ProcessDeclAttributeList(S, New, Attr); 4662 4663 // If we're declaring or defining a tag in function prototype scope 4664 // in C, note that this type can only be used within the function. 4665 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 4666 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 4667 4668 // Set the lexical context. If the tag has a C++ scope specifier, the 4669 // lexical context will be different from the semantic context. 4670 New->setLexicalDeclContext(CurContext); 4671 4672 // Mark this as a friend decl if applicable. 4673 if (TUK == TUK_Friend) 4674 New->setObjectOfFriendDecl(/* PreviouslyDeclared = */ PrevDecl != NULL); 4675 4676 // Set the access specifier. 4677 if (!Invalid && TUK != TUK_Friend) 4678 SetMemberAccessSpecifier(New, PrevDecl, AS); 4679 4680 if (TUK == TUK_Definition) 4681 New->startDefinition(); 4682 4683 // If this has an identifier, add it to the scope stack. 4684 if (TUK == TUK_Friend) { 4685 // We might be replacing an existing declaration in the lookup tables; 4686 // if so, borrow its access specifier. 4687 if (PrevDecl) 4688 New->setAccess(PrevDecl->getAccess()); 4689 4690 // Friend tag decls are visible in fairly strange ways. 4691 if (!CurContext->isDependentContext()) { 4692 DeclContext *DC = New->getDeclContext()->getLookupContext(); 4693 DC->makeDeclVisibleInContext(New, /* Recoverable = */ false); 4694 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC)) 4695 PushOnScopeChains(New, EnclosingScope, /* AddToContext = */ false); 4696 } 4697 } else if (Name) { 4698 S = getNonFieldDeclScope(S); 4699 PushOnScopeChains(New, S); 4700 } else { 4701 CurContext->addDecl(New); 4702 } 4703 4704 // If this is the C FILE type, notify the AST context. 4705 if (IdentifierInfo *II = New->getIdentifier()) 4706 if (!New->isInvalidDecl() && 4707 New->getDeclContext()->getLookupContext()->isTranslationUnit() && 4708 II->isStr("FILE")) 4709 Context.setFILEDecl(New); 4710 4711 OwnedDecl = true; 4712 return DeclPtrTy::make(New); 4713} 4714 4715void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 4716 AdjustDeclIfTemplate(TagD); 4717 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4718 4719 // Enter the tag context. 4720 PushDeclContext(S, Tag); 4721 4722 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 4723 FieldCollector->StartClass(); 4724 4725 if (Record->getIdentifier()) { 4726 // C++ [class]p2: 4727 // [...] The class-name is also inserted into the scope of the 4728 // class itself; this is known as the injected-class-name. For 4729 // purposes of access checking, the injected-class-name is treated 4730 // as if it were a public member name. 4731 CXXRecordDecl *InjectedClassName 4732 = CXXRecordDecl::Create(Context, Record->getTagKind(), 4733 CurContext, Record->getLocation(), 4734 Record->getIdentifier(), 4735 Record->getTagKeywordLoc(), 4736 Record); 4737 InjectedClassName->setImplicit(); 4738 InjectedClassName->setAccess(AS_public); 4739 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 4740 InjectedClassName->setDescribedClassTemplate(Template); 4741 PushOnScopeChains(InjectedClassName, S); 4742 assert(InjectedClassName->isInjectedClassName() && 4743 "Broken injected-class-name"); 4744 } 4745 } 4746} 4747 4748void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD, 4749 SourceLocation RBraceLoc) { 4750 AdjustDeclIfTemplate(TagD); 4751 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 4752 Tag->setRBraceLoc(RBraceLoc); 4753 4754 if (isa<CXXRecordDecl>(Tag)) 4755 FieldCollector->FinishClass(); 4756 4757 // Exit this scope of this tag's definition. 4758 PopDeclContext(); 4759 4760 // Notify the consumer that we've defined a tag. 4761 Consumer.HandleTagDeclDefinition(Tag); 4762} 4763 4764// Note that FieldName may be null for anonymous bitfields. 4765bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 4766 QualType FieldTy, const Expr *BitWidth, 4767 bool *ZeroWidth) { 4768 // Default to true; that shouldn't confuse checks for emptiness 4769 if (ZeroWidth) 4770 *ZeroWidth = true; 4771 4772 // C99 6.7.2.1p4 - verify the field type. 4773 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 4774 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 4775 // Handle incomplete types with specific error. 4776 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 4777 return true; 4778 if (FieldName) 4779 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 4780 << FieldName << FieldTy << BitWidth->getSourceRange(); 4781 return Diag(FieldLoc, diag::err_not_integral_type_anon_bitfield) 4782 << FieldTy << BitWidth->getSourceRange(); 4783 } 4784 4785 // If the bit-width is type- or value-dependent, don't try to check 4786 // it now. 4787 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 4788 return false; 4789 4790 llvm::APSInt Value; 4791 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 4792 return true; 4793 4794 if (Value != 0 && ZeroWidth) 4795 *ZeroWidth = false; 4796 4797 // Zero-width bitfield is ok for anonymous field. 4798 if (Value == 0 && FieldName) 4799 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 4800 4801 if (Value.isSigned() && Value.isNegative()) { 4802 if (FieldName) 4803 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 4804 << FieldName << Value.toString(10); 4805 return Diag(FieldLoc, diag::err_anon_bitfield_has_negative_width) 4806 << Value.toString(10); 4807 } 4808 4809 if (!FieldTy->isDependentType()) { 4810 uint64_t TypeSize = Context.getTypeSize(FieldTy); 4811 if (Value.getZExtValue() > TypeSize) { 4812 if (FieldName) 4813 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 4814 << FieldName << (unsigned)TypeSize; 4815 return Diag(FieldLoc, diag::err_anon_bitfield_width_exceeds_type_size) 4816 << (unsigned)TypeSize; 4817 } 4818 } 4819 4820 return false; 4821} 4822 4823/// ActOnField - Each field of a struct/union/class is passed into this in order 4824/// to create a FieldDecl object for it. 4825Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 4826 SourceLocation DeclStart, 4827 Declarator &D, ExprTy *BitfieldWidth) { 4828 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 4829 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 4830 AS_public); 4831 return DeclPtrTy::make(Res); 4832} 4833 4834/// HandleField - Analyze a field of a C struct or a C++ data member. 4835/// 4836FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 4837 SourceLocation DeclStart, 4838 Declarator &D, Expr *BitWidth, 4839 AccessSpecifier AS) { 4840 IdentifierInfo *II = D.getIdentifier(); 4841 SourceLocation Loc = DeclStart; 4842 if (II) Loc = D.getIdentifierLoc(); 4843 4844 DeclaratorInfo *DInfo = 0; 4845 QualType T = GetTypeForDeclarator(D, S, &DInfo); 4846 if (getLangOptions().CPlusPlus) 4847 CheckExtraCXXDefaultArguments(D); 4848 4849 DiagnoseFunctionSpecifiers(D); 4850 4851 if (D.getDeclSpec().isThreadSpecified()) 4852 Diag(D.getDeclSpec().getThreadSpecLoc(), diag::err_invalid_thread); 4853 4854 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 4855 ForRedeclaration); 4856 4857 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4858 // Maybe we will complain about the shadowed template parameter. 4859 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 4860 // Just pretend that we didn't see the previous declaration. 4861 PrevDecl = 0; 4862 } 4863 4864 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 4865 PrevDecl = 0; 4866 4867 bool Mutable 4868 = (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable); 4869 SourceLocation TSSL = D.getSourceRange().getBegin(); 4870 FieldDecl *NewFD 4871 = CheckFieldDecl(II, T, DInfo, Record, Loc, Mutable, BitWidth, TSSL, 4872 AS, PrevDecl, &D); 4873 if (NewFD->isInvalidDecl() && PrevDecl) { 4874 // Don't introduce NewFD into scope; there's already something 4875 // with the same name in the same scope. 4876 } else if (II) { 4877 PushOnScopeChains(NewFD, S); 4878 } else 4879 Record->addDecl(NewFD); 4880 4881 return NewFD; 4882} 4883 4884/// \brief Build a new FieldDecl and check its well-formedness. 4885/// 4886/// This routine builds a new FieldDecl given the fields name, type, 4887/// record, etc. \p PrevDecl should refer to any previous declaration 4888/// with the same name and in the same scope as the field to be 4889/// created. 4890/// 4891/// \returns a new FieldDecl. 4892/// 4893/// \todo The Declarator argument is a hack. It will be removed once 4894FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 4895 DeclaratorInfo *DInfo, 4896 RecordDecl *Record, SourceLocation Loc, 4897 bool Mutable, Expr *BitWidth, 4898 SourceLocation TSSL, 4899 AccessSpecifier AS, NamedDecl *PrevDecl, 4900 Declarator *D) { 4901 IdentifierInfo *II = Name.getAsIdentifierInfo(); 4902 bool InvalidDecl = false; 4903 if (D) InvalidDecl = D->isInvalidType(); 4904 4905 // If we receive a broken type, recover by assuming 'int' and 4906 // marking this declaration as invalid. 4907 if (T.isNull()) { 4908 InvalidDecl = true; 4909 T = Context.IntTy; 4910 } 4911 4912 // C99 6.7.2.1p8: A member of a structure or union may have any type other 4913 // than a variably modified type. 4914 if (T->isVariablyModifiedType()) { 4915 bool SizeIsNegative; 4916 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 4917 SizeIsNegative); 4918 if (!FixedTy.isNull()) { 4919 Diag(Loc, diag::warn_illegal_constant_array_size); 4920 T = FixedTy; 4921 } else { 4922 if (SizeIsNegative) 4923 Diag(Loc, diag::err_typecheck_negative_array_size); 4924 else 4925 Diag(Loc, diag::err_typecheck_field_variable_size); 4926 InvalidDecl = true; 4927 } 4928 } 4929 4930 // Fields can not have abstract class types 4931 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 4932 AbstractFieldType)) 4933 InvalidDecl = true; 4934 4935 bool ZeroWidth = false; 4936 // If this is declared as a bit-field, check the bit-field. 4937 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth, &ZeroWidth)) { 4938 InvalidDecl = true; 4939 DeleteExpr(BitWidth); 4940 BitWidth = 0; 4941 ZeroWidth = false; 4942 } 4943 4944 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, DInfo, 4945 BitWidth, Mutable); 4946 if (InvalidDecl) 4947 NewFD->setInvalidDecl(); 4948 4949 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 4950 Diag(Loc, diag::err_duplicate_member) << II; 4951 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 4952 NewFD->setInvalidDecl(); 4953 } 4954 4955 if (getLangOptions().CPlusPlus) { 4956 QualType EltTy = Context.getBaseElementType(T); 4957 4958 CXXRecordDecl* CXXRecord = cast<CXXRecordDecl>(Record); 4959 4960 if (!T->isPODType()) 4961 CXXRecord->setPOD(false); 4962 if (!ZeroWidth) 4963 CXXRecord->setEmpty(false); 4964 4965 if (const RecordType *RT = EltTy->getAs<RecordType>()) { 4966 CXXRecordDecl* RDecl = cast<CXXRecordDecl>(RT->getDecl()); 4967 4968 if (!RDecl->hasTrivialConstructor()) 4969 CXXRecord->setHasTrivialConstructor(false); 4970 if (!RDecl->hasTrivialCopyConstructor()) 4971 CXXRecord->setHasTrivialCopyConstructor(false); 4972 if (!RDecl->hasTrivialCopyAssignment()) 4973 CXXRecord->setHasTrivialCopyAssignment(false); 4974 if (!RDecl->hasTrivialDestructor()) 4975 CXXRecord->setHasTrivialDestructor(false); 4976 4977 // C++ 9.5p1: An object of a class with a non-trivial 4978 // constructor, a non-trivial copy constructor, a non-trivial 4979 // destructor, or a non-trivial copy assignment operator 4980 // cannot be a member of a union, nor can an array of such 4981 // objects. 4982 // TODO: C++0x alters this restriction significantly. 4983 if (Record->isUnion()) { 4984 // We check for copy constructors before constructors 4985 // because otherwise we'll never get complaints about 4986 // copy constructors. 4987 4988 const CXXSpecialMember invalid = (CXXSpecialMember) -1; 4989 4990 CXXSpecialMember member; 4991 if (!RDecl->hasTrivialCopyConstructor()) 4992 member = CXXCopyConstructor; 4993 else if (!RDecl->hasTrivialConstructor()) 4994 member = CXXDefaultConstructor; 4995 else if (!RDecl->hasTrivialCopyAssignment()) 4996 member = CXXCopyAssignment; 4997 else if (!RDecl->hasTrivialDestructor()) 4998 member = CXXDestructor; 4999 else 5000 member = invalid; 5001 5002 if (member != invalid) { 5003 Diag(Loc, diag::err_illegal_union_member) << Name << member; 5004 DiagnoseNontrivial(RT, member); 5005 NewFD->setInvalidDecl(); 5006 } 5007 } 5008 } 5009 } 5010 5011 // FIXME: We need to pass in the attributes given an AST 5012 // representation, not a parser representation. 5013 if (D) 5014 // FIXME: What to pass instead of TUScope? 5015 ProcessDeclAttributes(TUScope, NewFD, *D); 5016 5017 if (T.isObjCGCWeak()) 5018 Diag(Loc, diag::warn_attribute_weak_on_field); 5019 5020 NewFD->setAccess(AS); 5021 5022 // C++ [dcl.init.aggr]p1: 5023 // An aggregate is an array or a class (clause 9) with [...] no 5024 // private or protected non-static data members (clause 11). 5025 // A POD must be an aggregate. 5026 if (getLangOptions().CPlusPlus && 5027 (AS == AS_private || AS == AS_protected)) { 5028 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 5029 CXXRecord->setAggregate(false); 5030 CXXRecord->setPOD(false); 5031 } 5032 5033 return NewFD; 5034} 5035 5036/// DiagnoseNontrivial - Given that a class has a non-trivial 5037/// special member, figure out why. 5038void Sema::DiagnoseNontrivial(const RecordType* T, CXXSpecialMember member) { 5039 QualType QT(T, 0U); 5040 CXXRecordDecl* RD = cast<CXXRecordDecl>(T->getDecl()); 5041 5042 // Check whether the member was user-declared. 5043 switch (member) { 5044 case CXXDefaultConstructor: 5045 if (RD->hasUserDeclaredConstructor()) { 5046 typedef CXXRecordDecl::ctor_iterator ctor_iter; 5047 for (ctor_iter ci = RD->ctor_begin(), ce = RD->ctor_end(); ci != ce;++ci){ 5048 const FunctionDecl *body = 0; 5049 ci->getBody(body); 5050 if (!body || 5051 !cast<CXXConstructorDecl>(body)->isImplicitlyDefined(Context)) { 5052 SourceLocation CtorLoc = ci->getLocation(); 5053 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5054 return; 5055 } 5056 } 5057 5058 assert(0 && "found no user-declared constructors"); 5059 return; 5060 } 5061 break; 5062 5063 case CXXCopyConstructor: 5064 if (RD->hasUserDeclaredCopyConstructor()) { 5065 SourceLocation CtorLoc = 5066 RD->getCopyConstructor(Context, 0)->getLocation(); 5067 Diag(CtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5068 return; 5069 } 5070 break; 5071 5072 case CXXCopyAssignment: 5073 if (RD->hasUserDeclaredCopyAssignment()) { 5074 // FIXME: this should use the location of the copy 5075 // assignment, not the type. 5076 SourceLocation TyLoc = RD->getSourceRange().getBegin(); 5077 Diag(TyLoc, diag::note_nontrivial_user_defined) << QT << member; 5078 return; 5079 } 5080 break; 5081 5082 case CXXDestructor: 5083 if (RD->hasUserDeclaredDestructor()) { 5084 SourceLocation DtorLoc = RD->getDestructor(Context)->getLocation(); 5085 Diag(DtorLoc, diag::note_nontrivial_user_defined) << QT << member; 5086 return; 5087 } 5088 break; 5089 } 5090 5091 typedef CXXRecordDecl::base_class_iterator base_iter; 5092 5093 // Virtual bases and members inhibit trivial copying/construction, 5094 // but not trivial destruction. 5095 if (member != CXXDestructor) { 5096 // Check for virtual bases. vbases includes indirect virtual bases, 5097 // so we just iterate through the direct bases. 5098 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) 5099 if (bi->isVirtual()) { 5100 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5101 Diag(BaseLoc, diag::note_nontrivial_has_virtual) << QT << 1; 5102 return; 5103 } 5104 5105 // Check for virtual methods. 5106 typedef CXXRecordDecl::method_iterator meth_iter; 5107 for (meth_iter mi = RD->method_begin(), me = RD->method_end(); mi != me; 5108 ++mi) { 5109 if (mi->isVirtual()) { 5110 SourceLocation MLoc = mi->getSourceRange().getBegin(); 5111 Diag(MLoc, diag::note_nontrivial_has_virtual) << QT << 0; 5112 return; 5113 } 5114 } 5115 } 5116 5117 bool (CXXRecordDecl::*hasTrivial)() const; 5118 switch (member) { 5119 case CXXDefaultConstructor: 5120 hasTrivial = &CXXRecordDecl::hasTrivialConstructor; break; 5121 case CXXCopyConstructor: 5122 hasTrivial = &CXXRecordDecl::hasTrivialCopyConstructor; break; 5123 case CXXCopyAssignment: 5124 hasTrivial = &CXXRecordDecl::hasTrivialCopyAssignment; break; 5125 case CXXDestructor: 5126 hasTrivial = &CXXRecordDecl::hasTrivialDestructor; break; 5127 default: 5128 assert(0 && "unexpected special member"); return; 5129 } 5130 5131 // Check for nontrivial bases (and recurse). 5132 for (base_iter bi = RD->bases_begin(), be = RD->bases_end(); bi != be; ++bi) { 5133 const RecordType *BaseRT = bi->getType()->getAs<RecordType>(); 5134 assert(BaseRT && "Don't know how to handle dependent bases"); 5135 CXXRecordDecl *BaseRecTy = cast<CXXRecordDecl>(BaseRT->getDecl()); 5136 if (!(BaseRecTy->*hasTrivial)()) { 5137 SourceLocation BaseLoc = bi->getSourceRange().getBegin(); 5138 Diag(BaseLoc, diag::note_nontrivial_has_nontrivial) << QT << 1 << member; 5139 DiagnoseNontrivial(BaseRT, member); 5140 return; 5141 } 5142 } 5143 5144 // Check for nontrivial members (and recurse). 5145 typedef RecordDecl::field_iterator field_iter; 5146 for (field_iter fi = RD->field_begin(), fe = RD->field_end(); fi != fe; 5147 ++fi) { 5148 QualType EltTy = Context.getBaseElementType((*fi)->getType()); 5149 if (const RecordType *EltRT = EltTy->getAs<RecordType>()) { 5150 CXXRecordDecl* EltRD = cast<CXXRecordDecl>(EltRT->getDecl()); 5151 5152 if (!(EltRD->*hasTrivial)()) { 5153 SourceLocation FLoc = (*fi)->getLocation(); 5154 Diag(FLoc, diag::note_nontrivial_has_nontrivial) << QT << 0 << member; 5155 DiagnoseNontrivial(EltRT, member); 5156 return; 5157 } 5158 } 5159 } 5160 5161 assert(0 && "found no explanation for non-trivial member"); 5162} 5163 5164/// TranslateIvarVisibility - Translate visibility from a token ID to an 5165/// AST enum value. 5166static ObjCIvarDecl::AccessControl 5167TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 5168 switch (ivarVisibility) { 5169 default: assert(0 && "Unknown visitibility kind"); 5170 case tok::objc_private: return ObjCIvarDecl::Private; 5171 case tok::objc_public: return ObjCIvarDecl::Public; 5172 case tok::objc_protected: return ObjCIvarDecl::Protected; 5173 case tok::objc_package: return ObjCIvarDecl::Package; 5174 } 5175} 5176 5177/// ActOnIvar - Each ivar field of an objective-c class is passed into this 5178/// in order to create an IvarDecl object for it. 5179Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 5180 SourceLocation DeclStart, 5181 DeclPtrTy IntfDecl, 5182 Declarator &D, ExprTy *BitfieldWidth, 5183 tok::ObjCKeywordKind Visibility) { 5184 5185 IdentifierInfo *II = D.getIdentifier(); 5186 Expr *BitWidth = (Expr*)BitfieldWidth; 5187 SourceLocation Loc = DeclStart; 5188 if (II) Loc = D.getIdentifierLoc(); 5189 5190 // FIXME: Unnamed fields can be handled in various different ways, for 5191 // example, unnamed unions inject all members into the struct namespace! 5192 5193 DeclaratorInfo *DInfo = 0; 5194 QualType T = GetTypeForDeclarator(D, S, &DInfo); 5195 5196 if (BitWidth) { 5197 // 6.7.2.1p3, 6.7.2.1p4 5198 if (VerifyBitField(Loc, II, T, BitWidth)) { 5199 D.setInvalidType(); 5200 DeleteExpr(BitWidth); 5201 BitWidth = 0; 5202 } 5203 } else { 5204 // Not a bitfield. 5205 5206 // validate II. 5207 5208 } 5209 5210 // C99 6.7.2.1p8: A member of a structure or union may have any type other 5211 // than a variably modified type. 5212 if (T->isVariablyModifiedType()) { 5213 Diag(Loc, diag::err_typecheck_ivar_variable_size); 5214 D.setInvalidType(); 5215 } 5216 5217 // Get the visibility (access control) for this ivar. 5218 ObjCIvarDecl::AccessControl ac = 5219 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 5220 : ObjCIvarDecl::None; 5221 // Must set ivar's DeclContext to its enclosing interface. 5222 Decl *EnclosingDecl = IntfDecl.getAs<Decl>(); 5223 DeclContext *EnclosingContext; 5224 if (ObjCImplementationDecl *IMPDecl = 5225 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5226 // Case of ivar declared in an implementation. Context is that of its class. 5227 ObjCInterfaceDecl* IDecl = IMPDecl->getClassInterface(); 5228 assert(IDecl && "No class- ActOnIvar"); 5229 EnclosingContext = cast_or_null<DeclContext>(IDecl); 5230 } else 5231 EnclosingContext = dyn_cast<DeclContext>(EnclosingDecl); 5232 assert(EnclosingContext && "null DeclContext for ivar - ActOnIvar"); 5233 5234 // Construct the decl. 5235 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, 5236 EnclosingContext, Loc, II, T, 5237 DInfo, ac, (Expr *)BitfieldWidth); 5238 5239 if (II) { 5240 NamedDecl *PrevDecl = LookupSingleName(S, II, LookupMemberName, 5241 ForRedeclaration); 5242 if (PrevDecl && isDeclInScope(PrevDecl, EnclosingContext, S) 5243 && !isa<TagDecl>(PrevDecl)) { 5244 Diag(Loc, diag::err_duplicate_member) << II; 5245 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 5246 NewID->setInvalidDecl(); 5247 } 5248 } 5249 5250 // Process attributes attached to the ivar. 5251 ProcessDeclAttributes(S, NewID, D); 5252 5253 if (D.isInvalidType()) 5254 NewID->setInvalidDecl(); 5255 5256 if (II) { 5257 // FIXME: When interfaces are DeclContexts, we'll need to add 5258 // these to the interface. 5259 S->AddDecl(DeclPtrTy::make(NewID)); 5260 IdResolver.AddDecl(NewID); 5261 } 5262 5263 return DeclPtrTy::make(NewID); 5264} 5265 5266void Sema::ActOnFields(Scope* S, 5267 SourceLocation RecLoc, DeclPtrTy RecDecl, 5268 DeclPtrTy *Fields, unsigned NumFields, 5269 SourceLocation LBrac, SourceLocation RBrac, 5270 AttributeList *Attr) { 5271 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 5272 assert(EnclosingDecl && "missing record or interface decl"); 5273 5274 // If the decl this is being inserted into is invalid, then it may be a 5275 // redeclaration or some other bogus case. Don't try to add fields to it. 5276 if (EnclosingDecl->isInvalidDecl()) { 5277 // FIXME: Deallocate fields? 5278 return; 5279 } 5280 5281 5282 // Verify that all the fields are okay. 5283 unsigned NumNamedMembers = 0; 5284 llvm::SmallVector<FieldDecl*, 32> RecFields; 5285 5286 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 5287 for (unsigned i = 0; i != NumFields; ++i) { 5288 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 5289 5290 // Get the type for the field. 5291 Type *FDTy = FD->getType().getTypePtr(); 5292 5293 if (!FD->isAnonymousStructOrUnion()) { 5294 // Remember all fields written by the user. 5295 RecFields.push_back(FD); 5296 } 5297 5298 // If the field is already invalid for some reason, don't emit more 5299 // diagnostics about it. 5300 if (FD->isInvalidDecl()) 5301 continue; 5302 5303 // C99 6.7.2.1p2: 5304 // A structure or union shall not contain a member with 5305 // incomplete or function type (hence, a structure shall not 5306 // contain an instance of itself, but may contain a pointer to 5307 // an instance of itself), except that the last member of a 5308 // structure with more than one named member may have incomplete 5309 // array type; such a structure (and any union containing, 5310 // possibly recursively, a member that is such a structure) 5311 // shall not be a member of a structure or an element of an 5312 // array. 5313 if (FDTy->isFunctionType()) { 5314 // Field declared as a function. 5315 Diag(FD->getLocation(), diag::err_field_declared_as_function) 5316 << FD->getDeclName(); 5317 FD->setInvalidDecl(); 5318 EnclosingDecl->setInvalidDecl(); 5319 continue; 5320 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 5321 Record && Record->isStruct()) { 5322 // Flexible array member. 5323 if (NumNamedMembers < 1) { 5324 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 5325 << FD->getDeclName(); 5326 FD->setInvalidDecl(); 5327 EnclosingDecl->setInvalidDecl(); 5328 continue; 5329 } 5330 // Okay, we have a legal flexible array member at the end of the struct. 5331 if (Record) 5332 Record->setHasFlexibleArrayMember(true); 5333 } else if (!FDTy->isDependentType() && 5334 RequireCompleteType(FD->getLocation(), FD->getType(), 5335 diag::err_field_incomplete)) { 5336 // Incomplete type 5337 FD->setInvalidDecl(); 5338 EnclosingDecl->setInvalidDecl(); 5339 continue; 5340 } else if (const RecordType *FDTTy = FDTy->getAs<RecordType>()) { 5341 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 5342 // If this is a member of a union, then entire union becomes "flexible". 5343 if (Record && Record->isUnion()) { 5344 Record->setHasFlexibleArrayMember(true); 5345 } else { 5346 // If this is a struct/class and this is not the last element, reject 5347 // it. Note that GCC supports variable sized arrays in the middle of 5348 // structures. 5349 if (i != NumFields-1) 5350 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 5351 << FD->getDeclName() << FD->getType(); 5352 else { 5353 // We support flexible arrays at the end of structs in 5354 // other structs as an extension. 5355 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 5356 << FD->getDeclName(); 5357 if (Record) 5358 Record->setHasFlexibleArrayMember(true); 5359 } 5360 } 5361 } 5362 if (Record && FDTTy->getDecl()->hasObjectMember()) 5363 Record->setHasObjectMember(true); 5364 } else if (FDTy->isObjCInterfaceType()) { 5365 /// A field cannot be an Objective-c object 5366 Diag(FD->getLocation(), diag::err_statically_allocated_object); 5367 FD->setInvalidDecl(); 5368 EnclosingDecl->setInvalidDecl(); 5369 continue; 5370 } else if (getLangOptions().ObjC1 && 5371 getLangOptions().getGCMode() != LangOptions::NonGC && 5372 Record && 5373 (FD->getType()->isObjCObjectPointerType() || 5374 FD->getType().isObjCGCStrong())) 5375 Record->setHasObjectMember(true); 5376 // Keep track of the number of named members. 5377 if (FD->getIdentifier()) 5378 ++NumNamedMembers; 5379 } 5380 5381 // Okay, we successfully defined 'Record'. 5382 if (Record) { 5383 Record->completeDefinition(Context); 5384 } else { 5385 ObjCIvarDecl **ClsFields = 5386 reinterpret_cast<ObjCIvarDecl**>(RecFields.data()); 5387 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 5388 ID->setIVarList(ClsFields, RecFields.size(), Context); 5389 ID->setLocEnd(RBrac); 5390 // Add ivar's to class's DeclContext. 5391 for (unsigned i = 0, e = RecFields.size(); i != e; ++i) { 5392 ClsFields[i]->setLexicalDeclContext(ID); 5393 ID->addDecl(ClsFields[i]); 5394 } 5395 // Must enforce the rule that ivars in the base classes may not be 5396 // duplicates. 5397 if (ID->getSuperClass()) { 5398 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 5399 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 5400 ObjCIvarDecl* Ivar = (*IVI); 5401 5402 if (IdentifierInfo *II = Ivar->getIdentifier()) { 5403 ObjCIvarDecl* prevIvar = 5404 ID->getSuperClass()->lookupInstanceVariable(II); 5405 if (prevIvar) { 5406 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 5407 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 5408 } 5409 } 5410 } 5411 } 5412 } else if (ObjCImplementationDecl *IMPDecl = 5413 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 5414 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 5415 for (unsigned I = 0, N = RecFields.size(); I != N; ++I) 5416 // Ivar declared in @implementation never belongs to the implementation. 5417 // Only it is in implementation's lexical context. 5418 ClsFields[I]->setLexicalDeclContext(IMPDecl); 5419 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 5420 } 5421 } 5422 5423 if (Attr) 5424 ProcessDeclAttributeList(S, Record, Attr); 5425} 5426 5427EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 5428 EnumConstantDecl *LastEnumConst, 5429 SourceLocation IdLoc, 5430 IdentifierInfo *Id, 5431 ExprArg val) { 5432 Expr *Val = (Expr *)val.get(); 5433 5434 llvm::APSInt EnumVal(32); 5435 QualType EltTy; 5436 if (Val) { 5437 if (Val->isTypeDependent()) 5438 EltTy = Context.DependentTy; 5439 else { 5440 // Make sure to promote the operand type to int. 5441 UsualUnaryConversions(Val); 5442 if (Val != val.get()) { 5443 val.release(); 5444 val = Val; 5445 } 5446 5447 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 5448 SourceLocation ExpLoc; 5449 if (!Val->isValueDependent() && 5450 VerifyIntegerConstantExpression(Val, &EnumVal)) { 5451 Val = 0; 5452 } else { 5453 EltTy = Val->getType(); 5454 } 5455 } 5456 } 5457 5458 if (!Val) { 5459 if (LastEnumConst) { 5460 // Assign the last value + 1. 5461 EnumVal = LastEnumConst->getInitVal(); 5462 ++EnumVal; 5463 5464 // Check for overflow on increment. 5465 if (EnumVal < LastEnumConst->getInitVal()) 5466 Diag(IdLoc, diag::warn_enum_value_overflow); 5467 5468 EltTy = LastEnumConst->getType(); 5469 } else { 5470 // First value, set to zero. 5471 EltTy = Context.IntTy; 5472 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 5473 } 5474 } 5475 5476 assert(!EltTy.isNull() && "Enum constant with NULL type"); 5477 5478 val.release(); 5479 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 5480 Val, EnumVal); 5481} 5482 5483 5484Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 5485 DeclPtrTy lastEnumConst, 5486 SourceLocation IdLoc, 5487 IdentifierInfo *Id, 5488 SourceLocation EqualLoc, ExprTy *val) { 5489 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 5490 EnumConstantDecl *LastEnumConst = 5491 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 5492 Expr *Val = static_cast<Expr*>(val); 5493 5494 // The scope passed in may not be a decl scope. Zip up the scope tree until 5495 // we find one that is. 5496 S = getNonFieldDeclScope(S); 5497 5498 // Verify that there isn't already something declared with this name in this 5499 // scope. 5500 NamedDecl *PrevDecl = LookupSingleName(S, Id, LookupOrdinaryName); 5501 if (PrevDecl && PrevDecl->isTemplateParameter()) { 5502 // Maybe we will complain about the shadowed template parameter. 5503 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 5504 // Just pretend that we didn't see the previous declaration. 5505 PrevDecl = 0; 5506 } 5507 5508 if (PrevDecl) { 5509 // When in C++, we may get a TagDecl with the same name; in this case the 5510 // enum constant will 'hide' the tag. 5511 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 5512 "Received TagDecl when not in C++!"); 5513 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 5514 if (isa<EnumConstantDecl>(PrevDecl)) 5515 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 5516 else 5517 Diag(IdLoc, diag::err_redefinition) << Id; 5518 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 5519 if (Val) Val->Destroy(Context); 5520 return DeclPtrTy(); 5521 } 5522 } 5523 5524 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 5525 IdLoc, Id, Owned(Val)); 5526 5527 // Register this decl in the current scope stack. 5528 if (New) 5529 PushOnScopeChains(New, S); 5530 5531 return DeclPtrTy::make(New); 5532} 5533 5534void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc, 5535 SourceLocation RBraceLoc, DeclPtrTy EnumDeclX, 5536 DeclPtrTy *Elements, unsigned NumElements, 5537 Scope *S, AttributeList *Attr) { 5538 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 5539 QualType EnumType = Context.getTypeDeclType(Enum); 5540 5541 if (Attr) 5542 ProcessDeclAttributeList(S, Enum, Attr); 5543 5544 // TODO: If the result value doesn't fit in an int, it must be a long or long 5545 // long value. ISO C does not support this, but GCC does as an extension, 5546 // emit a warning. 5547 unsigned IntWidth = Context.Target.getIntWidth(); 5548 unsigned CharWidth = Context.Target.getCharWidth(); 5549 unsigned ShortWidth = Context.Target.getShortWidth(); 5550 5551 // Verify that all the values are okay, compute the size of the values, and 5552 // reverse the list. 5553 unsigned NumNegativeBits = 0; 5554 unsigned NumPositiveBits = 0; 5555 5556 // Keep track of whether all elements have type int. 5557 bool AllElementsInt = true; 5558 5559 for (unsigned i = 0; i != NumElements; ++i) { 5560 EnumConstantDecl *ECD = 5561 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5562 if (!ECD) continue; // Already issued a diagnostic. 5563 5564 // If the enum value doesn't fit in an int, emit an extension warning. 5565 const llvm::APSInt &InitVal = ECD->getInitVal(); 5566 assert(InitVal.getBitWidth() >= IntWidth && 5567 "Should have promoted value to int"); 5568 if (InitVal.getBitWidth() > IntWidth) { 5569 llvm::APSInt V(InitVal); 5570 V.trunc(IntWidth); 5571 V.extend(InitVal.getBitWidth()); 5572 if (V != InitVal) 5573 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 5574 << InitVal.toString(10); 5575 } 5576 5577 // Keep track of the size of positive and negative values. 5578 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 5579 NumPositiveBits = std::max(NumPositiveBits, 5580 (unsigned)InitVal.getActiveBits()); 5581 else 5582 NumNegativeBits = std::max(NumNegativeBits, 5583 (unsigned)InitVal.getMinSignedBits()); 5584 5585 // Keep track of whether every enum element has type int (very commmon). 5586 if (AllElementsInt) 5587 AllElementsInt = ECD->getType() == Context.IntTy; 5588 } 5589 5590 // Figure out the type that should be used for this enum. 5591 // FIXME: Support -fshort-enums. 5592 QualType BestType; 5593 unsigned BestWidth; 5594 5595 bool Packed = Enum->getAttr<PackedAttr>() ? true : false; 5596 5597 if (NumNegativeBits) { 5598 // If there is a negative value, figure out the smallest integer type (of 5599 // int/long/longlong) that fits. 5600 // If it's packed, check also if it fits a char or a short. 5601 if (Packed && NumNegativeBits <= CharWidth && NumPositiveBits < CharWidth) { 5602 BestType = Context.SignedCharTy; 5603 BestWidth = CharWidth; 5604 } else if (Packed && NumNegativeBits <= ShortWidth && 5605 NumPositiveBits < ShortWidth) { 5606 BestType = Context.ShortTy; 5607 BestWidth = ShortWidth; 5608 } 5609 else if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 5610 BestType = Context.IntTy; 5611 BestWidth = IntWidth; 5612 } else { 5613 BestWidth = Context.Target.getLongWidth(); 5614 5615 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 5616 BestType = Context.LongTy; 5617 else { 5618 BestWidth = Context.Target.getLongLongWidth(); 5619 5620 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 5621 Diag(Enum->getLocation(), diag::warn_enum_too_large); 5622 BestType = Context.LongLongTy; 5623 } 5624 } 5625 } else { 5626 // If there is no negative value, figure out which of uint, ulong, ulonglong 5627 // fits. 5628 // If it's packed, check also if it fits a char or a short. 5629 if (Packed && NumPositiveBits <= CharWidth) { 5630 BestType = Context.UnsignedCharTy; 5631 BestWidth = CharWidth; 5632 } else if (Packed && NumPositiveBits <= ShortWidth) { 5633 BestType = Context.UnsignedShortTy; 5634 BestWidth = ShortWidth; 5635 } 5636 else if (NumPositiveBits <= IntWidth) { 5637 BestType = Context.UnsignedIntTy; 5638 BestWidth = IntWidth; 5639 } else if (NumPositiveBits <= 5640 (BestWidth = Context.Target.getLongWidth())) { 5641 BestType = Context.UnsignedLongTy; 5642 } else { 5643 BestWidth = Context.Target.getLongLongWidth(); 5644 assert(NumPositiveBits <= BestWidth && 5645 "How could an initializer get larger than ULL?"); 5646 BestType = Context.UnsignedLongLongTy; 5647 } 5648 } 5649 5650 // Loop over all of the enumerator constants, changing their types to match 5651 // the type of the enum if needed. 5652 for (unsigned i = 0; i != NumElements; ++i) { 5653 EnumConstantDecl *ECD = 5654 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 5655 if (!ECD) continue; // Already issued a diagnostic. 5656 5657 // Standard C says the enumerators have int type, but we allow, as an 5658 // extension, the enumerators to be larger than int size. If each 5659 // enumerator value fits in an int, type it as an int, otherwise type it the 5660 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 5661 // that X has type 'int', not 'unsigned'. 5662 if (ECD->getType() == Context.IntTy) { 5663 // Make sure the init value is signed. 5664 llvm::APSInt IV = ECD->getInitVal(); 5665 IV.setIsSigned(true); 5666 ECD->setInitVal(IV); 5667 5668 if (getLangOptions().CPlusPlus) 5669 // C++ [dcl.enum]p4: Following the closing brace of an 5670 // enum-specifier, each enumerator has the type of its 5671 // enumeration. 5672 ECD->setType(EnumType); 5673 continue; // Already int type. 5674 } 5675 5676 // Determine whether the value fits into an int. 5677 llvm::APSInt InitVal = ECD->getInitVal(); 5678 bool FitsInInt; 5679 if (InitVal.isUnsigned() || !InitVal.isNegative()) 5680 FitsInInt = InitVal.getActiveBits() < IntWidth; 5681 else 5682 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 5683 5684 // If it fits into an integer type, force it. Otherwise force it to match 5685 // the enum decl type. 5686 QualType NewTy; 5687 unsigned NewWidth; 5688 bool NewSign; 5689 if (FitsInInt) { 5690 NewTy = Context.IntTy; 5691 NewWidth = IntWidth; 5692 NewSign = true; 5693 } else if (ECD->getType() == BestType) { 5694 // Already the right type! 5695 if (getLangOptions().CPlusPlus) 5696 // C++ [dcl.enum]p4: Following the closing brace of an 5697 // enum-specifier, each enumerator has the type of its 5698 // enumeration. 5699 ECD->setType(EnumType); 5700 continue; 5701 } else { 5702 NewTy = BestType; 5703 NewWidth = BestWidth; 5704 NewSign = BestType->isSignedIntegerType(); 5705 } 5706 5707 // Adjust the APSInt value. 5708 InitVal.extOrTrunc(NewWidth); 5709 InitVal.setIsSigned(NewSign); 5710 ECD->setInitVal(InitVal); 5711 5712 // Adjust the Expr initializer and type. 5713 if (ECD->getInitExpr()) 5714 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, 5715 CastExpr::CK_IntegralCast, 5716 ECD->getInitExpr(), 5717 /*isLvalue=*/false)); 5718 if (getLangOptions().CPlusPlus) 5719 // C++ [dcl.enum]p4: Following the closing brace of an 5720 // enum-specifier, each enumerator has the type of its 5721 // enumeration. 5722 ECD->setType(EnumType); 5723 else 5724 ECD->setType(NewTy); 5725 } 5726 5727 Enum->completeDefinition(Context, BestType); 5728} 5729 5730Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 5731 ExprArg expr) { 5732 StringLiteral *AsmString = cast<StringLiteral>(expr.takeAs<Expr>()); 5733 5734 FileScopeAsmDecl *New = FileScopeAsmDecl::Create(Context, CurContext, 5735 Loc, AsmString); 5736 CurContext->addDecl(New); 5737 return DeclPtrTy::make(New); 5738} 5739 5740void Sema::ActOnPragmaWeakID(IdentifierInfo* Name, 5741 SourceLocation PragmaLoc, 5742 SourceLocation NameLoc) { 5743 Decl *PrevDecl = LookupSingleName(TUScope, Name, LookupOrdinaryName); 5744 5745 if (PrevDecl) { 5746 PrevDecl->addAttr(::new (Context) WeakAttr()); 5747 } else { 5748 (void)WeakUndeclaredIdentifiers.insert( 5749 std::pair<IdentifierInfo*,WeakInfo> 5750 (Name, WeakInfo((IdentifierInfo*)0, NameLoc))); 5751 } 5752} 5753 5754void Sema::ActOnPragmaWeakAlias(IdentifierInfo* Name, 5755 IdentifierInfo* AliasName, 5756 SourceLocation PragmaLoc, 5757 SourceLocation NameLoc, 5758 SourceLocation AliasNameLoc) { 5759 Decl *PrevDecl = LookupSingleName(TUScope, AliasName, LookupOrdinaryName); 5760 WeakInfo W = WeakInfo(Name, NameLoc); 5761 5762 if (PrevDecl) { 5763 if (!PrevDecl->hasAttr<AliasAttr>()) 5764 if (NamedDecl *ND = dyn_cast<NamedDecl>(PrevDecl)) 5765 DeclApplyPragmaWeak(TUScope, ND, W); 5766 } else { 5767 (void)WeakUndeclaredIdentifiers.insert( 5768 std::pair<IdentifierInfo*,WeakInfo>(AliasName, W)); 5769 } 5770} 5771